cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Model parameters in the context of late time cosmic acceleration in $f(Q,T)$ gravity
Creators: name: Pati, Laxmipriya
name: Mishra, B.
name: Tripathy, S. K.
Publisher: name: arXiv
Year: 2021
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: The dynamical aspects of some accelerating models are investigated in the framework of an extension of symmetric teleparllel gravity dubbed as f(Q,T) gravity. In this gravity theory, the usual Ricci tensor in the geometrical action is replaced by a functional f(Q,T) where Q is the non-metricity and T is the trace of the energy-momentum tensor. Two different functional forms are considered in the present work. In order to model the Universe, we have considered a signature flipping deceleration parameter simulated by a hybrid scale factor (HSF). The dynamical parameters of the model are derived and analysed. We discuss the role of the parameter space in getting viable cosmological models. It is found that, the models may be useful as suitable geometrical alternatives to the usual dark energy approach.
description: 9 pages, 7 figures
Aproximación a los estudios sobre la economía en la Segunda República española hasta 1936
Creators: name: Martin-De-Santos, Ines
name: Martin-Vega, Arturo
Publisher: name: figshare
Year: 2021
Subjects: subject: 140203 Economic History
subject: FOS: Economics and business
subject: Economics
subject: 140207 Financial Economics
subject: 130103 Higher Education
subject: FOS: Educational sciences
subject: 140101 History of Economic Thought
subject: Sociology
subject: FOS: Sociology

description: Los datos macroeconómicos sobre la economía española durante la Segunda República no son del todo bien conocidos, y la interpretación de los hechos históricos, a partir de las cifras obtenidas, resulta divergente y tendenciosa. Los problemas sociales, derivados fundamentalmente de las profundas desigualdades económicas, se intentaron paliar con leyes apresuradas que en muchos casos supusieron declaraciones de buenas intenciones. España arrastraba el declive económico internacional que comenzó a sentirse a finales de la dictadura del general Primo de Rivera. La política económica se desarrolló al amparo de la Constitución y, a pesar de las discrepancias entre el primer y el segundo bienio, fue continuista respecto a la etapa anterior y, en general, si no justa a veces, sirvió al menos para evitar la desestabilización del sistema financiero. En todo caso, resultó insuficiente para realizarse plenamente, debido sobre todo a los abundantes cambios gubernamentales, y mediatizada por una crisis social de mayor transcendencia que relegó los problemas económicos a un segundo plano.
Replicating agent-based simulation models of herding in financial markets
Creators: name: Liu, Xin
Publisher: name: Lancaster University
Year: 2021

description: Agent-based simulation of herding in financial markets varies in the herding and market mechanism. Replication studies are a cornerstone of the scientific method although it is not applied very often. The research aims to obtain a greater understanding of herding and the related stylised facts, assess the herding models’ reproducibility, and find ways to improve reproducibility by replicating two herding models. The first herding mechanism factor (Tedeschi et al., 2012) controls the extent of the neighbour’s influence on the expected returns and hence on the trading decisions. The market mechanism is an artificial market where agents submit either ask or bid orders into the order book, and they trade between themselves. The second replicating herding mechanism (Lux and Marchesi, 2000) is based on transition probabilities to decide whether agents are fundamentalists, optimistic or pessimistic chartists. The market mechanism is demand and supply. The first replicating study fails to produce the original results, whereas the second does have similar findings to the original paper. The second model’s description is done by following the recent STRESS guidelines for specifying models. The guidelines help to cover everything needed for describing the second model. Then features from the STRESS and ODD guidelines are combined to give a slightly revised guideline with a defined structure. This is considered to give an improvement. Both models have fat tails, and only the second model has volatility clustering. The behaviour of the second model that gives the volatility clustering is called on-off intermittency. This is analysed in detail to understand how the model enters and leaves periods of high volatility. The conclusions are that randomness causes the model to move into high volatility, which happens when the percentage of noise traders is high, and the price effect in the model soon returns the model back to low volatility.
Local coherence and deflation of the low quark modes in lattice QCD
Creators: name: Lüscher, Martin
Publisher: name: arXiv
Year: 2007
Subjects: subject: High Energy Physics - Lattice (hep-lat)
subject: FOS: Physical sciences

description: The spontaneous breaking of chiral symmetry in QCD is known to be linked to a non-zero density of eigenvalues of the massless Dirac operator near the origin. Numerical studies of two-flavour QCD now suggest that the low quark modes are locally coherent to a certain extent. As a consequence, the modes can be simultaneously deflated, using local projectors, with a total computational effort proportional to the lattice volume (rather than its square). Deflation has potentially many uses in lattice QCD. The technique is here worked out for the case of quark propagator calculations, where large speed-up factors and a flat scaling behaviour with respect to the quark mass are achieved.
description: Plain TeX, 23 pages, 4 figures included; minor text modifications; version published in JHEP
Queueing for ergodic arrivals and services
Creators: name: Gyorfi, L.
name: Morvai, G.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Probability (math.PR)
subject: Information Theory (cs.IT)
subject: FOS: Mathematics
subject: FOS: Computer and information sciences

description: In this paper we revisit the results of Loynes (1962) on stability of queues for ergodic arrivals and services, and show examples when the arrivals are bounded and ergodic, the service rate is constant, and under stability the limit distribution has larger than exponential tail.
description: Queueing for ergodic arrivals and services. In Limit Theorems in Probability and Statistics, I. Berkes E. Csaki, M. Csorgo (Eds.), pp. 127-141, J. Bolyai Mathematical Society, 2002
Implementation of a Fourier Matched Filter in CMB Analyses. Application to ISW Studies
Creators: name: Hernandez-Monteagudo, Carlos
Publisher: name: arXiv
Year: 2008
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: Aims: Implement a matched filter (MF) cross-correlation algorithm in multipole space and compare it to the standard Angular Cross Power Spectrum (ACPS) method. Apply both methods on a Integrated Sachs Wolfe (ISW) - Large Scale Structure (LSS) cross correlation scenario and study how sky masks influence the multipole range where signal arises and its comparison to theoretical predictions. Methods: The MF requires the inversion of a multipole covariance matrix that if $f_{sky} \lt 1$ is generally non-diagonal and singular. We use a SVD approach that focuses on those modes carrying most of the information. We compare the MF to the ACPS in ISW-LSS Monte Carlo simulations, paying attention on the effect that a limited sky coverage has on the cross-correlation results. Results: Within the linear data model for which the MF is defined, the MF performs comparatively better than the ACPS for smaller values of $f_{sky}$ and scale dependent (non-Poissonian) noise fields. In the context of ISW studies both methods are comparable, although the MF performs slightly more sensitively under more restrictive masks. A preliminary study predicts that most of the ISW--LSS cross correlation S/N ratio should be found in the very large scales (50% of the S/N at $l\lt 10$, 90% at $l\lt 40-50$), and this is confirmed by Monte Carlo simulations. The statistical significance of our cross-correlation statistics reaches its maximum when considering $l\in [2,l_{max}]$, with $l_{max} \in[5,40]$ for all values of $f_{sky}$ observed, despite of the smoothing and power aliasing that aggressive masks introduce in Fourier space. This $l$-confinement of the ISW-LSS cross correlation should enable a safe distinction from other secondary effects arising at smaller angular scales.
description: 9 pages, 5 figures, submitted to A&A
Improving the accuracy of the neuroevolution machine learning potential for multi-component systems
Creators: name: Fan, Zheyong
Publisher: name: arXiv
Year: 2021
Subjects: subject: Computational Physics (physics.comp-ph)
subject: FOS: Physical sciences

description: In a previous paper [Fan Z \textit{et al}. 2021 Phys. Rev. B, \textbf{104}, 104309], we developed the neuroevolution potential (NEP), a framework of training neural network based machine-learning potentials using a natural evolution strategy and performing molecular dynamics (MD) simulations using the trained potentials. The atom-environment descriptor in NEP was constructed based on a set of radial and angular functions. For multi-component systems, all the radial functions between two atoms are multiplied by some fixed factors that depend on the types of the two atoms only. In this paper, we introduce an improved descriptor for multi-component systems, in which different radial functions are multiplied by different factors that are also optimized during the training process, and show that it can significantly improve the regression accuracy without increasing the computational cost in MD simulations.
description: 7 pages, 8 figures, code and data available
On Becoming What the Story Needs
Creators: name: Sumara, Dennis
Publisher: name: Journal of Applied Hermeneutics
Year: 2021

description: Abstract In this article, I use Derrida’s (1978) conceptualizing of différance to inform hermeneutic readings of my queer archive of deferrals. These readings show some of the complex ways remembered and forgotten experiences of learning, teaching, and schooling are inevitably shaped by heteronormativity. My interest in différance is informed and maintained by my active resistance to how the subjects needed by those stories can lose track of their deferrals in ways that can reposition the normative within the counternormative and vice versa. I conclude by discussing how creative re-storying can support acts of remembering, forgetting, and fictionalizing that can lead to hermeneutic insight. Keywords queer, archive, subjectivity, story, difference, normative, hermeneutics, writing, teaching, reading
description: Journal of Applied Hermeneutics, 2021: 2021
Revitalising Traditional Malay Woodcarving through Design for Sustainability
Creators: name: Mohamed Yusof, Shahrul Anuwar
Publisher: name: Lancaster University
Year: 2021
Subjects: Design for sustainability
Malay woodcarving
craft revitalisation

description: In the age of global industrialisation and mass production, traditional crafts offer an example of long-standing ‘local’ approaches to material culture that are often socially, environmentally and economically reifying. However, evidence suggests that traditional crafts struggle to survive, and this is also the case in Malaysia. Moreover, there has been limited academic investigation into the meaning and manifestation of sustainable development among craftspeople, and the relationship of this to traditional Malaysian heritage. The central aim of this thesis is to investigate the potential and provide an in-depth understanding of the relationship between Malay craft and design for sustainability, focusing especially on traditional woodcarving. The key research question is; How can woodcarving, as a culturally significant craft practice, be revitalised in Malaysia through effective design contributions and in accordance with sustainable design principles? Data was collected via semi-structured interviews in Malaysia with 37 respondents from three groups of stakeholders in the craft industry: producers, supporters, and buyers; two case studies were also carried out in Malaysia. The relationships reviewed between various themes and sub-themes and organising them as a coherent whole constitutes an extensive qualitative study. Five main research findings are identified, which informed the development of a Craft Revitalisation Framework for Malay Traditional Woodcarving. This framework identifies key factors and their relationships that can inform context appropriate revitalisation strategies among the various stakeholders. The study recognises the need to involve appropriate stakeholders, including designers, in the development of such strategies. The conclusions from this study provide a better understanding on the significance, value and meaning of traditional Malay crafts, including woodcarving, in accordance with the principles of sustainability. In addition, it offers a useful tool and a well-founded direction to help ensure the future viability of craft practices.
Beam Performance of Tracking Detectors with Industrially Produced GEM Foils
Creators: name: Simon, Frank
name: Kelsey, James
name: Kohl, Michael
name: Majka, Richard
name: Plesko, Miro
name: Sakuma, Tai
name: Smirnov, Nikolai
name: Spinka, Harold
name: Surrow, Bernd
name: Underwood, David
Publisher: name: arXiv
Year: 2008
Subjects: subject: Instrumentation and Detectors (physics.ins-det)
subject: FOS: Physical sciences

description: Three Gas-Electron-Multiplier tracking detectors with an active area of 10 cm x 10 cm and a two-dimensional, laser-etched orthogonal strip readout have been tested extensively in particle beams at the Meson Test Beam Facility at Fermilab. These detectors used GEM foils produced by Tech-Etch, Inc. They showed an efficiency in excess of 95% and spatial resolution better than 70 um. The influence of the angle of incidence of particles on efficiency and spatial resolution was studied in detail.
description: 8 pages, 9 figures, accepted by Nuclear Instruments and Methods in Physics Research A
Development of frequency division multiplexing readout for a large transition edge sensor array for space
Creators: name: , Qian
Publisher: name: Zenodo
Year: 2021
Subjects: Far-infrared astronomy, superconducting, transition edge sensor, multiplexing, SQUID, readout

description: The light in sub-millimeter and far-Infrared (FIR) wavelengths from deep space can travel in an incredibly long distance and contains rich, unique information, which can help astronomers to reveal the history of the universe and answer outstanding questions such as the origin of galaxies, stars, and planets. Sensitive transition edge sensor (TES) bolometers in combination with frequency division multiplexing (FDM) readout system that can read out multiple pixels simultaneously are the candidate detector technology for several space missions operated at sub-millimeter and FIR wavelengths. My thesis reports the study and development of an FDM-readout system for TES bolometers, containing five main scientific sub-projects focusing on building systematically a readout demonstration system. Characterizing the noise of the readout system is essential. Chapter 3 and 4 report studies of the noise from room- and cryogenic-temperature electrical components, respectively. Chapter 5 presents a map of all pixels in the FDM-system, aiming to reduce the unwanted noise between pixels within a TES bolometer array. Chapter 6 demonstrates an FDM-system that can read out 60 low noise TES bolometers simultaneously. The readout noise of the FDM-system is lower than the noise of highly sensitive detectors and that the sensitivities measured when all pixels in operation are the same as what measured when only one pixel is operated. Chapter 7 shows further improved results on electrical-crosstalk performance and stability of the FDM-system compared to Chapter 6. We report a full demonstration of the FDM-system in the lab, opening the door to the readout for space observatories.
Pore structure and electrochemical properties of CNT-based electrodes studied by in situ small/wide angle X-ray scattering
Creators: name: Santos, Cleis
name: Senokos, Evgeny
name: Fernández-Toribio, Juan Carlos
name: Ridruejo, Álvaro
name: Marcilla, Rebeca
name: Vilatela, Juan José
Publisher: name: arXiv
Year: 2021
Subjects: subject: Applied Physics (physics.app-ph)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: Macroscopic ensembles of nanocarbons, such as fibres of carbon nanotubes (CNT), are characterised by a complex hierarchical structure combining coherent crystalline regions with a large porosity arising from imperfect packing of the large rigid building blocks. Such structure is at the centre of a wide range of charge storage and transfer processes when CNT fibres are used as electrodes and/or current collectors. This work introduces a method based on wide and small-angle X-ray scattering (WAXS/SAXS) to obtain structural descriptors of CNT fibres and which enables in situ characterisation during electrochemical processes. It enables accurate determination of parameters such as specific surface area, average pore size and average bundle size from SAXS data after correction for scattering from density fluctuations arising from imperfect packing of graphitic planes. In situ and ex situ WAXS/SAXS measurements during electrochemical swelling of CNT fibre electrodes in ionic liquid provide continuous monitoring of the increase in effective surface area caused by electrostatic separation of CNT bundles in remarkable agreement with capacitance changes measured independently. Relative contributions from quantum and Helmholtz capacitance to total capacitance remaining fairly constant. The WAXS/SAXS analysis is demonstrated for fibres of either multi- and single-walled CNTs, and is expected to be generally applicable to operando studies on nanocarbon-based electrodes used in batteries, actuators and other applications
Conjugate Points in Length Spaces
Creators: name: Shankar, Krishnan
name: Sormani, Christina
Publisher: name: arXiv
Year: 2007
Subjects: subject: Metric Geometry (math.MG)
subject: FOS: Mathematics

description: In this paper we extend the concept of a conjugate point in a Riemannian manifold to complete length spaces (also known as geodesic spaces). In particular, we introduce symmetric conjugate points and ultimate conjugate points. We then generalize the long homotopy lemma of Klingenberg to this setting as well as the injectivity radius estimate also due to Klingenberg which was used to produce closed geodesics or conjugate points on Riemannian manifolds. Our versions apply in this more general setting. We next focus on ${\rm CBA}(κ)$ spaces, proving Rauch-type comparison theorems. In particular, much like the Riemannian setting, we prove an Alexander-Bishop theorem stating that there are no ultimate conjugate points less than $π$ apart in a ${\rm CBA}(1)$ space. We also prove a relative Rauch comparison theorem to precisely estimate the distance between nearby geodesics. We close with applications and open problems.
description: 47 pages, 10 figures, added references and comments to prior notions
Parameterization of solar irradiation under clear skies
Creators: name: Mächler, Meinrad A.
Publisher: name: University of British Columbia
Year: 2010

description: This study compares 5 existing insolation models on three levels of complexity. The model by Leckner represents a spectral integration model, the models by Bird & Hulstrom, Davies & Hay and by Hoyt are parameterization models and the model of A.S.H.R.A.E is a simple seasonal model. The emphasis of the comparison was kept on the attenuation by atmospheric aerosols as well as on the aspect of the scattered radiation. No new model will be proposed; instead, several improvements to increase the accuracy or to make the application easier will be presented, notably for the determination of aerosol attenuation. Simplification has been achieved by using the correlation between horizontal ground visibility and aerosol attenuation, resulting in easy-to-handle equations. While most models received only minor changes it was necessary to restructure the A.S.H.R.A.E. algorithm substantially.
Photons from relativistic nuclear collisions
Creators: name: Vormann, Hannah
name: Reichert, Tom
name: Spieles, Christian
name: Steinheimer, Jan
name: Bleicher, Marcus
Publisher: name: arXiv
Year: 2021
Subjects: subject: Popular Physics (physics.pop-ph)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: Collisions of atomic nuclei at relativistic velocities allow to recreate the conditions encountered in neutron stars or in the early universe micro-seconds after the Big Bang. These reactions are performed in today's largest accelerator facilities, e.g. at CERN in Geneva, at the Relativistic Heavy Ion Collider at Brookhaven, NY or in the planned FAIR facility in Darmstadt Germany. During such a collision the matter is heated up to hundreds of MeV (billions of degrees) and compressed to densities of $3-10$ times the density inside ordinary atomic nuclei (i.e. $10^{17}-10^{18}$ kg/m$^3$). Usually these collisions are studied via the measurement of a multitude of strongly interacting particles, called hadrons, that are emitted at the end of the collision. However, also some photons are created. These photons are of special interest as they allow to look into the early stage of the collisions, because they are only very weakly (namely only electro-magnetically) interacting with the hadrons of the created fireball. This paper elucidates the physics of the photons and what can be learned from them.
description: 8 pages, 5 figures Additional section: "VI. What can be learned from this project?"; results unchanged
The few-body problem in terms of correlated gaussians
Creators: name: Silvestre-Brac, Bernard
name: Mathieu, Vincent
Publisher: name: arXiv
Year: 2007
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: Computational Physics (physics.comp-ph)
subject: FOS: Physical sciences

description: In their textbook, Suzuki and Varga [Y. Suzuki and K. Varga, {\em Stochastic Variational Approach to Quantum-Mechanical Few-Body Problems} (Springer, Berlin, 1998)] present the stochastic variational method in a very exhaustive way. In this framework, the so-called correlated gaussian bases are often employed. General formulae for the matrix elements of various operators can be found in the textbook. However the Fourier transform of correlated gaussians and their application to the management of a relativistic kinetic energy operator are missing and cannot be found in the literature. In this paper we present these interesting formulae. We give also a derivation for new formulations concerning central potentials; the corresponding formulae are more efficient numerically than those presented in the textbook.
description: 10 pages
Libitioides Roewer 1912
Creators: name: Kury, Adriano B.
name: Medrano, Miguel
Publisher: name: Zenodo
Year: 2023
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Arachnida
Opiliones
Cosmetidae
Libitioides

description: Examples of misidentifications of the American species of Libitioides
There are several examples of species of “ Vonones ” reported in websites dedicated to imaging wildlife. USA-based users are predominant in this kind of site (e.g., iNat reports that there are 14 million observations from the American territory, https://www.inaturalist.org/posts/26101-world-inaturalist-participation). Accordingly, the names of the commonest or most conspicuous American species have a broader exposure in several reports and may end up as part of the popular culture. On Table 1, a few examples illustrate the wide use of misidentified “ Vonones ” spp.
description: Published as part of Kury, Adriano B. & Medrano, Miguel, 2023, Once upon a time in America: recognition of the species of Libitioides from USA, with comments on other American Cosmetidae (Opiliones, Laniatores), pp. 101-141 in European Journal of Taxonomy 875 (1) on page 103, DOI: 10.5852/ejt.2023.875.2143, http://zenodo.org/record/8064424
On the role of continuous symmetries in the solution of the 3D Euler fluid equations and related models
Creators: name: Bustamante, Miguel D.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Fluid Dynamics (physics.flu-dyn)
subject: Analysis of PDEs (math.AP)
subject: FOS: Physical sciences
subject: FOS: Mathematics

description: We review and apply the continuous symmetry approach to find the solution of the 3D Euler fluid equations in several instances of interest, via the construction of constants of motion and infinitesimal symmetries, without recourse to Noether's theorem. We show that the vorticity field is a symmetry of the flow, so if the flow admits another symmetry then a Lie algebra of new symmetries can be constructed. For steady Euler flows this leads directly to the distinction of (non-)Beltrami flows: an example is given where the topology of the spatial manifold determines whether extra symmetries can be constructed. Next, we study the stagnation-point-type exact solution of the 3D Euler fluid equations introduced by Gibbon et al. (Physica D, vol.132, 1999, pp.497-510) along with a one-parameter generalisation of it introduced by Mulungye et al. (J. Fluid Mech., vol.771, 2015, pp.468-502). Applying the symmetry approach to these models allows for the explicit integration of the fields along pathlines, revealing a fine structure of blowup for the vorticity, its stretching rate, and the back-to-labels map, depending on the value of the free parameter and on the initial conditions. Finally, we produce explicit blowup exponents and prefactors for a generic type of initial conditions.
description: Accepted for publication in Philosophical Transactions A
Quantum communication between trapped ions through a dissipative environment
Creators: name: Ng, H. T.
name: Bose, S.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We study two trapped ions coupled to the axial phonon modes of a one-dimensional Coulomb crystal. This system is formally equivalent to the "two spin-boson" model. We propose a scheme to dynamically generate a maximally entangled state of two ions within a decoherence-free subspace. Here the phononic environment of the trapped ions, whatever its temperature and number of modes, serves as the entangling bus. The efficient production of the pure singlet state can be exploited to perform short-ranged quantum communication which is essential in building up a large-scale quantum computer.
description: 4 pages, 2 figures
A study of B-splines and their applications to surface design and manufacture
Creators: name: Bedi, Sanjeev
Publisher: name: University of British Columbia
Year: 2010

description: Compound curved surfaces are frequently encountered in engineering applications, such as marine propellers, turbines, ship hulls, aeroplane fuselages and automobile bodies. In the manufacture of such items the surface definition is required in a smoothly changing form without surface oscillations and irregularities. Frequently, however, the surfaces are defined by measured prototype data, which may be sparse in nature and have attendant measurement errors. In such instances the data has to be approximated and possibly smoothed by a series of curves of some known form. There are a number of types of curves available for curve fitting in CAD/CAM work. In this work the basis and properties of B-spline curve fitting are established and evaluated in relation to other curve fitting techniques. A series of trial shapes, or bench marks, were devised which showed that B-splines generated the smoothest curves and are very suitable for computer-aided-design applications. B-splines, with other types of spline curves, form the basis of a new computer-aided-machining program called G-SURF. The surface is defined within G-SURF as a grid of orthogonal space curves and is machined using an end milling cutter inclined at a predetermined angle to the surface normals. The end mill thus cuts on the leading or trailing edge (as appropriate) and is able to remove material very efficiently at a full and preselected material cutting speed. Within this work G-SURF has been used to design and produce a series of trial objects, including a 3ft. ship hull and a chain-saw guide bar. They have served to prove and test the G-SURF program.
On Some Additive Properties of Multiplicative Subsemigroups of Semirings and Arithmetic Applications I
Creators: name: Qiu, Derong
Publisher: name: arXiv
Year: 2009
Subjects: subject: Number Theory (math.NT)
subject: Commutative Algebra (math.AC)
subject: FOS: Mathematics
subject: 11P32 (primary), 05D05, 11A41, 11T55, 13A99, 16H05 (Secondary)

description: In this paper, we consider a question of sum-keeping about a multiplicative subsemigroup and its generator subsets in a semiring, and develop some elementary (collapse) process of the sum-keeping retraction through subsets until one minimal generators subset. As an application, we study and analyze several classical problems in additive number theory on the semiring of non-negative integers by this algebraic and combinatory idea, and provide new proofs in more simple and direct way for several classical results in number theory. Some further questions are also presented and discussed.
description: 38 pages; The title is changed, the abstract is slightly changed. Section 1 is rewritten, some notations in section 3 are simplified
Influence of Pore Surface Chemistry on the Rotational Dynamics of Nanoconfined Water
Creators: name: Malfait, Benjamin
name: Jani, Aicha
name: Mietner, Jakob Benedikt
name: Lefort, Ronan
name: Huber, Patrick
name: Fröba, Michael
name: Morineau, Denis
Publisher: name: arXiv
Year: 2021
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: Chemical Physics (physics.chem-ph)
subject: FOS: Physical sciences

description: We have investigated the dynamics of water confined in mesostructured porous silicas (SBA-15, MCM-41) and four periodic mesoporous organosilicas (PMOs) by dielectric relaxation spectroscopy. The influence of water-surface interaction has been controlled by the carefully designed surface chemistry of PMOs that involved organic bridges connecting silica moieties with different repetition lengths, hydrophilicity and H-bonding capability. Relaxation processes attributed to the rotational motions of non-freezable water located in the vicinity of the pore surface were studied in the temperature range from 140 K to 225 K. Two distinct situations were achieved depending on the hydration level: at low relative humidity (33% RH), water formed a non-freezable layer adsorbed on the pore surface. At 75% RH, water formed an interfacial liquid layer sandwiched between the pore surface and the ice crystallized in the pore center. In the two cases, the study revealed different water dynamics and different dependence on the surface chemistry. We infer that these findings illustrate the respective importance of water-water and water-surface interactions in determining the dynamics of the interfacial liquid-like water and the adsorbed water molecules, as well as the nature of the different H-bonding sites present on the pore surface.
description: Journal of Physical Chemistry C, American Chemical Society, In press
On the Rosenau equation: Lie symmetries, periodic solutions and solitary wave dynamics
Creators: name: Demirci, Ali
name: Hasanoglu, Yasin
name: Muslu, Gulcin M.
name: Ozemir, Cihangir
Publisher: name: arXiv
Year: 2021
Subjects: subject: Analysis of PDEs (math.AP)
subject: Numerical Analysis (math.NA)
subject: FOS: Mathematics

description: In this paper, we first consider the Rosenau equation with the quadratic nonlinearity and identify its Lie symmetry algebra. We obtain reductions of the equation to ODEs, and find periodic analytical solutions in terms of elliptic functions. Then, considering a general power-type nonlinearity, we prove the non-existence of solitary waves for some parameters using Pohozaev type identities. The Fourier pseudo-spectral method is proposed for the Rosenau equation with this single power type nonlinearity. In order to investigate the solitary wave dynamics, we generate the solitary wave profile as an initial condition by using the Petviashvili's method. Then the evolution of the single solitary wave and overtaking collision of solitary waves are investigated by various numerical experiments.
description: Published version with minor changes
Scaling laws and higher-order effects in Coulomb excitation of neutron halo nuclei
Creators: name: Typel, S.
name: Baur, G.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Nuclear Theory (nucl-th)
subject: Nuclear Experiment (nucl-ex)
subject: FOS: Physical sciences

description: Essential properties of halo nuclei can be described in terms of a few low-energy constants. For neutron halo nuclei, analytical results can be found for wave functions and electromagnetic transition matrix-elements in simple but well-adapted models. These wave functions can be used to study nuclear reactions; an especially simple and instructive example is Coulomb excitation. A systematic expansion in terms of small parameters can be given. We present scaling laws for excitation amplitudes and cross sections. The results can be used to analyze experiments like ${}^{11}$Be Coulomb excitation. They also serve as benchmark tests for more involved reaction theories.
description: 7 pages, 2 figures, submitted to European Physical Journal A
The $S_8$ Tension in Light of Updated Redshift-Space Distortion Data and PAge Approximation
Creators: name: Huang, Lu
name: Huang, Zhiqi
name: Zhou, Huan
name: Li, Zhuoyang
Publisher: name: arXiv
Year: 2021
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences
subject: J.2
subject: 83F05

description: One of the most prominent challenges to the standard Lambda cold dark matter ($Λ$CDM) cosmology is the tension between the structure growth parameter $S_8$ constrained by the cosmic microwave background (CMB) data and the smaller one suggested by the cosmic shear data. Recent studies show that, for $Λ$CDM cosmology, redshift-space distortion (RSD) data also prefers a smaller $S_8$ that is $\sim 2$-$3σ$ lower than the CMB value, but the result is sensitive to the cosmological model. In the present work we update the RSD constraint on $S_8$ with the most up-to-date RSD data set where the correlation between data points are properly taken into account. To reduce the model dependence, we add in our Monte Carlo Markov Chain calculation the most up-to-date data sets of Type Ia supernovae (SN) and baryon acoustic oscillations (BAO), whose correlation with RSD is also taken into account, to constrain the background geometry. For $Λ$CDM cosmology we find $S_8= 0.812 \pm 0.026$, which is $\sim 2σ$ larger than previous studies, and hence is consistent with the CMB constraint. By replacing $Λ$CDM with the Parameterization based on cosmic Age (PAge), an almost model-independent description of the late universe, we find that the RSD + SN + BAO constraint on $S_8$ is insensitive to the cosmological model.
description: 6 pages, 3 figures; to appear on SCPMA
X-ray detection of the substellar twin 2MASS J11011926-7732383 AB
Creators: name: Stelzer, B.
name: Micela, G.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: 2MASS J11011926-7732383 AB (hereafter 2M1101AB), located in the Cha I star forming region, is a rare wide-separation brown dwarf binary. XMM-Newton and Chandra observations of 2M1101AB have allowed us to examine the influence of physical parameters (mass, bolometric luminosity and effective temperature) on X-ray emission from a coeval pair of substellar objects. The spatial resolution of XMM-Newton is not sufficient to separate contributions from the two components in the binary. The X-ray source detected with XMM-Newton has a column density compatible with the infrared extinction of component A. On the other hand, the binary is resolved with Chandra, and the bulk of the X-ray emission is clearly associated with the photospherically cooler component B. These apparently contradictory results point at strong variability of 2M1101's X-ray emission. Combined with previous sensitive X-ray observations from low-mass members of ChaI, we find a decline of X-ray luminosity with decreasing (sub)stellar mass that is typical for star forming regions. 2M1101B is the coolest (spectral type M8.25) and least massive brown dwarf of ChaI detected in X-rays so far. It is also among the youngest (~1 Myr) substellar ChaI members, and therefore relatively luminous. Most bona fide brown dwarfs of Cha I have remained below the sensitivity limits of available X-ray observations, because of their low luminosity associated with higher age.
description: accepted for publication in Astronomy & Astrophysics
Noncompact $\mathbf{CP}^N$ as a phase space of superintegrable systems
Creators: name: Khastyan, Erik
name: Nersessian, Armen
name: Shmavonyan, Hovhannes
Publisher: name: arXiv
Year: 2020
Subjects: subject: Mathematical Physics (math-ph)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We propose the description of superintegrable models with dynamical $so(1.2)$ symmetry, and of the generic superintegrable deformations of oscillator and Coulomb systems in terms of higher-dimensional Klein model (the non-compact analog of complex projective space) playing the role of phase space. We present the expressions of the constants of motion of these systems via Killing potentials defining the $su(N.1)$ isometries of the Kähler structure.
description: 11 pages, misprints corrected
Diffusion, super-diffusion and coalescence from single step
Creators: name: Gabrielli, Andrea
name: Cecconi, Fabio
Publisher: name: arXiv
Year: 2007
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: FOS: Physical sciences

description: From the exact single step evolution equation of the two-point correlation function of a particle distribution subjected to a stochastic displacement field $\bu(\bx)$, we derive different dynamical regimes when $\bu(\bx)$ is iterated to build a velocity field. First we show that spatially uncorrelated fields $\bu(\bx)$ lead to both standard and anomalous diffusion equation. When the field $\bu(\bx)$ is spatially correlated each particle performs a simple free Brownian motion, but the trajectories of different particles result to be mutually correlated. The two-point statistical properties of the field $\bu(\bx)$ induce two-point spatial correlations in the particle distribution satisfying a simple but non-trivial diffusion-like equation. These displacement-displacement correlations lead the system to three possible regimes: coalescence, simple clustering and a combination of the two. The existence of these different regimes, in the one-dimensional system, is shown through computer simulations and a simple theoretical argument.
description: RevTeX (iopstyle) 19 pages, 5 eps-figures
Temnocheilus imazighenorum Korn & Klug 2023, sp. nov.
Creators: name: Korn, Dieter
name: Klug, Christian
Publisher: name: Zenodo
Year: 2023
Subjects: Biodiversity
Taxonomy
Animalia
Mollusca
Cephalopoda
Nautilida
Koninckioceratidae
Temnocheilus
Temnocheilus imazighenorum

description: Temnocheilus imazighenorum sp. nov.
urn:lsid:zoobank.org:act: 84E662FC-B0AB-4F6C-A69D-FD82103B2127
Fig. 6; Table 1
Diagnosis
Species of Temnocheilus with thinly pachyconic, subevolute conch (ww/dm ~0.65; uw/dm ~0.38); whorl profile moderately depressed, trapezoidal (ww/wh ~1.85), venter flattened, ventrolateral shoulder angular with elongated longitudinal nodes. Whorls very weakly embracing. Shell surface almost smooth.
Etymology
Named after the Imazighen, the ethnic group indigenous to the Maghreb region of North Africa.
Material examined
Holotype
MOROCCO • Anti-Atlas, east of Gara el Itima, 36 km east-northeast of Taouz; uppermost Zrigat Formation; Ebbighausen & Korn 2004 Coll.; illustrated in Fig. 6; MB.C.31291.
Description
Holotype MB.C.31291 is a somewhat weathered specimen 105 mm in diameter, allowing the study of two whorls (Fig. 6). The conch is barrel-shaped, thinly pachyconic and subevolute (ww/dm=0.64; uw/ dm =0.38) with a very high coiling rate (WER= 2.28) and weakly embracing whorls. The whorl profile is trapezoidal with a flattened venter, an angular ventrolateral shoulder and flattened flanks plus umbilical wall. On the penultimate whorl, the ventrolateral shoulder bears eight longitudinally elongate nodes per half volution; they are much weaker on the last volution. The shell surface appears to be smooth.
Remarks
Temnocheilus imazighenorum sp. nov. is similar to T. coronatus but differs in the more compressed conch (ww/dm ~ 0.65 in T. imazighenorum but ~ 0.75 in T. coronatus), in the less depressed whorl profile (ww/wh ~ 1.85 in T. imazighenorum but ~ 2.25 in T. coronatus) and in the more flattened venter, which is broadly arched in T. coronatus. Temnocheilus coronatiformae differs in the slightly convex venter.
description: Published as part of Korn, Dieter & Klug, Christian, 2023, Early Carboniferous coiled nautiloids from the Anti-Atlas (Morocco), pp. 156-194 in European Journal of Taxonomy 885 on pages 163-164, DOI: 10.5852/ejt.2023.885.2199, http://zenodo.org/record/8222417
Scalar Lumps with Two Horizons
Creators: name: Lavrelashvili, George
name: Lehners, Jean-Luc
Publisher: name: arXiv
Year: 2021
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We study generalisations of the Schwarzschild-de Sitter solution in the presence of a scalar field with a potential barrier. These static, spherically symmetric solutions have two horizons, in between which the scalar interpolates at least once across the potential barrier, thus developing a lump. In part, we recover solutions discussed earlier in the literature and for those we clarify their properties. But we also find a new class of solutions in which the scalar lump curves the spacetime sufficiently strongly so as to change the nature of the erstwhile cosmological horizon into an additional trapped horizon, resulting in a scalar lump surrounded by two black holes. These new solutions appear in a wide range of the parameter space of the potential. We also discuss (challenges for) the application of all of these solutions to black hole seeded vacuum decay.
description: 32 pages, 13 figures, v2: replaced with published version
Does Charge Contribute to the Frame Dragging of Spacetime?
Creators: name: Mirza, Babur M.
Publisher: name: arXiv
Year: 2008
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: Electrically charged systems bound by a strong gravitational force can sustain a huge amount of electric charge (up to 10^20C) against Coulomb repulsion. General relativistically such systems form a stable hydrostatic configuration both in the non-rotating and rotating cases. Here we study the effects of electric charge (electric energy density) on the spacetime outside a rotating electrically charged system bound by a strong gravitational force. In particular we investigate the effect of charge density on frame-dragging of spacetime in the exterior region. Using the coupled Einstein-Maxwell equations it is found that in the slow rotation approximation charge accumulations not only acts like an additional mass, thus modifying the spherically symmetric part of the spacetime, the electric charge also contributes directly to the dragging of spacetime. A modified Lense-Thirring formula for the spacetime frame dragging frequency is obtained.
description: 6 pages, 3 figures
An integrated whispering-gallery-mode resonator for solid-state coherent quantum photonics
Creators: name: Brooks, Arianne
name: Chu, Xiao-Liu
name: Liu, Zhe
name: Schott, Rudiger
name: Ludwig, Arne
name: Wieck, Andreas D.
name: Midolo, Leonardo
name: Lodahl, Peter
name: Rotenberg, Nir
Publisher: name: arXiv
Year: 2021
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Tailored photonic cavities allow enhancing light-matter interaction ultimately to create a fully coherent quantum interface. Here, we report on an integrated microdisk cavity containing self-assembled quantum dots to coherently route photons between different access waveguides. We measure a Purcell factor of $F_{exp}=6.9\pm0.9$ for a cavity quality factor of about 10,000, allowing us to observe clear signatures of coherent scattering of photons by the quantum dots. We show how this integrated system can coherently re-route photons between the drop and bus ports, and how this routing is controlled by detuning the quantum dot and resonator, or through the strength of the excitation beam, where a critical photon number less than one photon per lifetime is required. We discuss the strengths and limitations of this approach, focusing on how the coherent scattering and single-photon nonlinearity can be used to increase the efficiency of quantum devices such as routers or Bell-state analyzers.
Measuring the surface stress polar dependence
Creators: name: Metois, J. J.
name: Saul, A.
name: Muller, P.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: While measurements of the polar dependence of the surface free energy are easily available, measurements of the whole polar dependence of the surface stress of a crystal do not exist. In this paper is presented a new procedure that allows, for the first time, the experimental determination of the surface stress polar dependence of a crystal. For this purpose (1) electromigration is used to control the kinetic faceting of surface orientations that belong to the equilibrium shape of the crystal and (2) for each destabilised surface, the period of faceting as well as the crystallographic angles of the appearing facets are measured by AFM. The so-obtained data lead to a set of equations whose mathematical solution, compatible with physical constraints, gives access to the surface stress polar dependence of the whole crystal and thus to a better understanding of surface stress properties.
description: 8 pages, 6 Figures
Local stress and superfluid properties of solid Helium-4
Creators: name: Pollet, L.
name: Boninsegni, M.
name: Kuklov, A. B.
name: Prokofev, N. V.
name: Svistunov, B. V.
name: Troyer, M.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: More than half a century ago Penrose asked: are the superfluid and solid state of matter mutually exclusive or do there exist "supersolid" materials where the atoms form a regular lattice and simultaneously flow without friction? Recent experiments provide evidence that supersolid behavior indeed exists in Helium-4 -- the most quantum material known in Nature. In this paper we show that large local strain in the vicinity of crystalline defects is the origin of supersolidity in Helium-4. Although ideal crystals of Helium-4 are not supersolid, the gap for vacancy creation closes when applying a moderate stress. While a homogeneous system simply becomes unstable at this point, the stressed core of crystalline defects (dislocations and grain boundaries) undergoes a radical transformation and can become superfluid.