cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Strong magnetic fields and pasta phases revisited
Creators: name: Scurto, Luigi
name: Pais, Helena
name: Gulminelli, Francesca
Publisher: name: arXiv
Year: 2022
Subjects: subject: Nuclear Theory (nucl-th)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: In this work, we compute the structure and composition of the inner crust of a neutron star in the presence of a strong magnetic field, such as it can be found in magnetars. To determine the geometry and characteristics of the crust inhomogeneities, we consider the compressible liquid drop model, where surface and Coulomb terms are included in the variational equations, and we compare our results with previous calculations based on more approximate treatments. For the equation of state (EoS), we consider two non-linear relativistic mean-field models with different slopes of the symmetry energy, and we show that the extension of the inhomogeneous region inside the star core due to the magnetic field strongly depends on the behavior of the symmetry energy in the crustal EoS. Finally, we argue that the extended spinodal instability observed in previous calculations can be related to the presence of small amplitude density fluctuations in the magnetar outer core, rather than to a thicker solid crust. The compressible liquid drop model formalism, while in overall agreement with the previous calculations, leads to a systematic suppression of the metastable solutions, thus allowing a more precise estimation of the crust-core transition density and pressure, and therefore a better estimation of the crustal radius.
description: 11 pages, 5 figures, 3 tables. Version published on Phys. Rev. C
Polaron contributions to the biexciton binding energies in self-assembled quantum dots
Creators: name: Machnikowski, Paweł
Publisher: name: arXiv
Year: 2010
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: The contribution to the biexciton binding energy in quantum dots resulting from the interaction with longitudinal optical phonons is estimated by performing the configuration--interaction calculation of the few-particle states in a simple model of the confining potential and including the phonon corrections by means of a perturbation theory. It is found that the polaron contribution tends to compensate the Coulomb-related biexciton shift (binding energy) and reduces its value by several to even 30%, depending on the material parameters of the system.
description: 4 pqges, 2 color figures; moderately modified version
Thermometry of Strongly Correlated Fermionic Quantum Systems using Impurity Probes
Creators: name: Mihailescu, George
name: Campbell, Steve
name: Mitchell, Andrew K.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Quantum Physics (quant-ph)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Quantum Gases (cond-mat.quant-gas)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We study quantum impurity models as a platform for quantum thermometry. A single quantum spin-1/2 impurity is coupled to an explicit, structured, fermionic thermal environment which we refer to as the environment or bath. We critically assess the thermometric capabilities of the impurity as a probe, when its coupling to the environment is of Ising or Kondo exchange type. In the Ising case, we find sensitivity equivalent to that of an idealized two-level system, with peak thermometric performance obtained at a temperature that scales linearly in the applied control field, independent of the coupling strength and environment spectral features. By contrast, a richer thermometric response can be realized for Kondo impurities, since strong probe-environment entanglement can then develop. At low temperatures, we uncover a regime with a universal thermometric response that is independent of microscopic details, controlled only by the low-energy spectral features of the environment. The many-body entanglement that develops in this regime means that low-temperature thermometry with a weakly applied control field is inherently less sensitive, while optimal sensitivity is recovered by suppressing the entanglement with stronger fields.
description: 16 pages, 5 figures. Close to published version
Exponential return to equilibrium for hypoelliptic quadratic systems
Creators: name: Ottobre, M.
name: Pavliotis, G. A.
name: Pravda-Starov, K.
Publisher: name: arXiv
Year: 2011
Subjects: subject: Mathematical Physics (math-ph)
subject: Spectral Theory (math.SP)
subject: FOS: Physical sciences
subject: FOS: Mathematics
subject: Primary: 35H10, 35P99, Secondary: 35Q82

description: We study the problem of convergence to equilibrium for evolution equations associated to general quadratic operators. Quadratic operators are non-selfadjoint differential operators with complex-valued quadratic symbols. Under appropriate assumptions, a complete description of the spectrum of such operators is given and the exponential return to equilibrium with sharp estimates on the rate of convergence is proven. Some applications to the study of chains of oscillators and the generalized Langevin equation are given.
description: 28 pages, 4 figures
Some mixed Hodge structure on l^2-cohomology of covering of Kähler manifolds
Creators: name: Dingoyan, Pascal
Publisher: name: arXiv
Year: 2010
Subjects: subject: Complex Variables (math.CV)
subject: FOS: Mathematics
subject: 58A14, 14F35, 32C35

description: We give methods to compute l^2-cohomology groups of a covering manifolds obtained by removing pullback of a (normal crossing) divisor to a covering of a compact Kähler manifold. We prove that in suitable quotient categories, these groups admit natural mixed Hodge structure whose graded pieces are given by expected Gysin maps.
description: 40 pages. This revised version will be published in Mathematische Annalen
Quantifying the development of small-scale fisheries on coral reefs, and their impact on habitats
Creators: name: Selgrath, Jennifer Coyle
Publisher: name: University of British Columbia
Year: 2017

description: Growing human populations place multiple pressures on social-ecological systems, including coastal oceans. However, the effects of long-term and/or overlapping stressors remain poorly understood, particularly over large spatial scales. My dissertation evaluated how pressures from fishing and co-occurring stressors correspond to current ecological conditions in the Danajon Bank, a coral reef ecosystem in the central Philippines. I used long-term local ecological knowledge (LEK) to map fishing practices (1950-2010) and high spatial resolution satellite imagery to map coastal habitats. This innovative suite of methods enabled me to examine patterns over broader spatial scales and longer time periods than those usually assessed. I met five primary objectives: (1) quantify the spatio-temporal dynamics of fishing effort and gear use; (2) examine the influence of fisheries governance; (3) map the spatial distribution of benthic (seafloor) habitats; (4) model the spatial distribution of living corals in relation to co-occurring stressors and biophysical conditions; and (5) explore the conservation implications of these relationships. While individuals’ fishing practices were fairly consistent over time, this small-scale fishery has changed dramatically. First, total fishing effort (days per year fished by all fishers) accelerated between 1960 and 2010 because of rapid growth in the number of fishers. Aggregate fishing effort increased almost 2.5-fold and spatially-explicit fishing effort increased over 20-fold. Second, the areal extent of fishing grounds expanded greatly. Third, use of fishing gears changed over time. Diversity of fishing gears increased, as did fishing effort with destructive, active, and non-selective gears. Considering the timing of these changes, I found a lasting influence of fishing policies, and small improvements in the sustainability of fishing gears following implementation of co-management. Finally, I found that the probability that an area supported living corals was affected by fishing through both long- & short-term mechanisms, and I documented strong coral-landscape relationships. My research demonstrates that to strengthen ocean conservation, it will be essential to reduce the frequency and intensity of stressors, remove some areas from exploitation, foster resilience traits of ecosystems, gather data to better understand systems, and strengthen the institutions that can support these endeavors.
L^3 estimates for an algebraic variable coefficient Wolff circular maximal function
Creators: name: Zahl, Joshua
Publisher: name: arXiv
Year: 2010
Subjects: subject: Classical Analysis and ODEs (math.CA)
subject: FOS: Mathematics
subject: 42B25

description: In 1997, Thomas Wolff proved sharp $L^3$ bounds for his circular maximal function, and in 1999, Kolasa and Wolff proved certain non-sharp $L^p$ inequalities for a broader class of maximal functions arising from curves of the form $\{Φ(x,\cdot)=r\}$, where $Φ(x,y)$ satisfied Sogge's cinematic curvature condition. Under the additional hypothesis that $Φ$ is algebraic, we obtain a sharp $L^3$ bound on the corresponding maximal function. Since the function $Φ(x,y)=|x-y|$ is algebraic and satisfies the cinematic curvature condition, our result generalizes Wolff's $L^3$ bound. The algebraicity condition allows us to employ the techniques of vertical cell decompositions and random sampling, which have been extensively developed in the computational geometry literature.
description: 26 pages, 2 figures
Spercheidae
Creators: name: Bilton, David T.
Publisher: name: Zenodo
Year: 2017
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Coleoptera
Spercheidae

description: Spercheidae   * Spercheus cerisyi Guérin-Méneville, 1842
A widespread Afrotropical species not apparently recorded previously in this province. Site 12.
description: Published as part of Bilton, David T., 2017, Water beetles from the Bokkeveld Plateau: a semi-arid hotspot of freshwater biodiversity in the Northern Cape of South Africa, pp. 191-214 in Zootaxa 4268 (2) on page 210, DOI: 10.11646/zootaxa.4268.2.2, http://zenodo.org/record/580190
Co-designing for a Hybrid Workplace Experience in Software Development
Creators: name: Wang, Zhendong
name: Chou, Yi-Hung
name: Fathi, Kayla
name: Schimmer, Tobias
name: Colligan, Peter
name: Redmiles, David
name: Prikladnicki, Rafael
Publisher: name: arXiv
Year: 2022
Subjects: subject: Software Engineering (cs.SE)
subject: FOS: Computer and information sciences

description: With increasing demands for flexible work models, many IT organizations have adapted to hybrid work that promises enhanced team productivity as well as work satisfaction. To achieve productive engineering practice, collaborative product innovation, and effective mentorship in the ensuing hybrid work, we introduce a workshop approach on co-designing for a hybrid workplace experience and provide implications for continuously improving collaborative software development at scale.
description: Accepted at IEEE Software
Gender Matters: Bringing in a Gender Structure Analysis. A Comment on “Paternal and Maternal Gatekeeping? Choreographing Care-giving in Families” by Tina Miller and “Rethinking Family Socialization to Gender through the Lens of Multi-local, Post-separation Families” by Laura Merla
Creators: name: Risman, Barbara J.
Publisher: name: Sociologica
Year: 2018
Subjects: gender; gender as a social structure; inequalities; family; feminism

description: In this comment, Risman suggests that both papers show definitely that gender still matters, but how it matters in families is consistently shifting. Both papers provide glimpses into how new family dynamics both reinforce and challenge gender inequality. Risman presents her theoretical framework of gender as a social structure and applies it to each article to analyze what the research teaches us about these families, and what questions remain unanswered.
description: Sociologica, Vol 12, No 3 (2018)
Pragmatism, Religion and Ethics: A Review Essay. H. Deuser et al, The Varieties of Transcendence: Pragmatism and the Theory of Religion, New York: Fordham University Press, 2016; N. Brunsveld, The Many Faces of Religious Truth: Hilary Putnam’s Pragmatic Pluralism on Religion, Leuven: Peeters, 2017; D.B. Heney, Toward a Pragmatist Metaethics, London: Routledge, 2016
Creators: name: Romania, Vincenzo
Publisher: name: Sociologica
Year: 2018
Subjects: pragmatism; ethics; religion; epistemology; social theory

description: In the last decades, pragmatism is consolidating its influence on social sciences, both in terms of epistemology and ontology. A series of recent philosophical publications deal with a rather classical pragmatist topic — the relationship between morality, religion, and truth — in quite a new shape. First, they deal with the conception of a pragmatist epistemology based on situated morality and truth aptness of moral judgments. Second, they propose a large reflection on the relationship between theology and pluralism in terms of truth regimes. Finally, they try to overcome the pitfalls of the Jamesian phenomenological conception of religion, through both the semiotic lens of Charles S. Peirce and the rediscovery of the Josiah Royce’s works. This paper uses the stimuli of the three books listed above to introduce the reader to a socio-philosophical perspective rather not considered in the European debate, despite its importance for the development of American sociology (symbolic interactionism, the School of Chicago, R.K. Merton, among the others) and for a variety of European scholars. A second objective is to understand how the problems pragmatist philosophers encounter in analysing the religious phenomena could help understanding the need for a multifactorial and multilevel explanation of religion and ethics. Finally, in the discussion, the author critically enlightens the need to avoid collapsing morality into religion — as sometimes pragmatists do — and extends and reframes Hans Joas’ appropriation of Mead and Durkheim in his pragmatist approach to religion and morality.
description: Sociologica, Vol 12, No 3 (2018)
On the nature of radio-wave radiation from particle cascades
Creators: name: James, Clancy W.
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: High Energy Physics - Experiment (hep-ex)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: The nature of the radio-wave radiation generated by particle cascades in both the Earth's atmosphere and dense media such as ice has, historically, been much debated. This situation changed in the early 2010's, with the community converging on the common terminology of "geomagnetic" and "Askaryan" radiation to describe the two emission mechanisms. However, this convergence arose from discussions at various conferences and workshops, and was ultimately reached through agreement between simulation codes and experimental measurements. In this article therefore, I use relatively simple geometrical arguments, and a minimum of calculations based on single particle tracks, to explain the nature of radiation from extensive air showers (EAS) and cascades in dense media such as ice. I identify well-determined frequency regimes where the radiation from the Askaryan effect will be bremsstrahlung-like and Cherenkov-like, being respectively below/above 1 GHz in EAS and 100 MHz in dense media; and where geomagnetic emission will be transverse-current-like and where it will resemble synchrotron radiation, respectively below/above a few GHz in EAS, depending on the height of cascade development. I suggest how these transitions in the nature of the emission may be experimentally observed.
description: 15 pages, 1 table, 8 figures, submitted to Physical Review D
Accurate holographic light potentials using pixel crosstalk modelling
Creators: name: Schroff, P.
name: La Rooij, A.
name: Haller, E.
name: Kuhr, S.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Optics (physics.optics)
subject: Quantum Gases (cond-mat.quant-gas)
subject: Atomic Physics (physics.atom-ph)
subject: FOS: Physical sciences

description: Arbitrary light potentials have proven to be a valuable and versatile tool in many quantum information and quantum simulation experiments with ultracold atoms. Using a phase-modulating spatial light modulator (SLM), we generate arbitrary light potentials holographically with measured efficiencies between $15\% - 40\% $ and an accuracy of below $2\% $ root-mean-squared error. Key to the high accuracy is the modelling of pixel crosstalk of the SLM on a sub-pixel scale which is relevant especially for large light potentials. We employ conjugate gradient minimisation to calculate the SLM phase pattern for a given target light potential after measuring the intensity and wavefront at the SLM. Further, we use camera feedback to reduce experimental errors, we remove optical vortices and investigate the difference between the angular spectrum method and the Fourier transform to simulate the propagation of light. Using a combination of all these techniques, we achieved more accurate and efficient light potentials compared to previous studies, and generated a series of potentials relevant for cold atom experiments.
Entrepreneurship in Cuba: Returns of Party Affiliation and Mobilization of Personal Contacts in Cuba
Creators: name: Romanò, Sara
Publisher: name: Sociologica
Year: 2018
Subjects: social capital; political capital; social mobility; transitional economies; Cuba

description: This manuscript focuses on factors — in particular, political credential and mobilization of personal contacts — associated to becoming a cuentapropista, namely a self-employed worker in the emerging private sector. Data were collected shortly before the launch of the recent reforms plan aiming at revitalizing the market-oriented reforms of the 1990s. The results suggest that being a member of the PCC is negatively associated to entering in the private sector. Older individuals and recipients of remittances have instead a higher probability to become a self-employed worker. Moreover, the results provide some support to previous findings that turning to personal ties — especially if strong — to successfully complete a job search, is a common practice in Cuba.
description: Sociologica, Vol 12, No 3 (2018)
Coralie radial velocity search for companions around evolved stars (CASCADES) II. Seismic masses for three red giants orbited by long-period massive planets
Creators: name: Buldgen, G.
name: Ottoni, G.
name: Pezzotti, C.
name: Lyttle, A.
name: Eggenberger, P.
name: Udry, S.
name: Ségransan, D.
name: Miglio, A.
name: Mayor, M.
name: Lovis, C.
name: Elsworth, Y.
name: Davies, G. R.
name: Ball, W. H.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: The advent of asteroseismology as the golden path to precisely characterize single stars naturally led to synergies with the field of exoplanetology. Today, the precise determination of stellar masses, radii and ages for exoplanet-host stars is a driving force in the development of dedicated software and techniques to achieve this goal. However, as various approaches exist, it is clear that they all have advantages and inconveniences and that there is a trade-off between accuracy, efficiency, and robustness of the techniques. We aim to compare and discuss various modelling techniques for exoplanet-host red giant stars for which TESS data are available. The results of the seismic modelling are then used to study the dynamical evolution and atmospheric evaporation of the planetary systems. We study, in detail, the robustness, accuracy and precision of various seismic modelling techniques when applied to four exoplanet-host red giants observed by TESS. We discuss the use of global seismic indexes, the use of individual radial frequencies and that of non-radial oscillations. In each case, we discuss the advantages and inconveniences of the modelling technique. We determine precise and accurate masses of exoplanet-host red giant stars orbited by long-period Jupiter-like planets using various modelling techniques. For each target, we also provide a model-independent estimate of the mass from a mean density inversion combined with radii values from Gaia and spectroscopic data. We show that no engulfment or migration is observed for these targets, even if their evolution is extended beyond their estimated seismic ages up the red giant branch.
description: Accepted for publication in Astronomy and Astrophysics. Part of the CASCADES series of papers
Law of large numbers for non-elliptic random walks in dynamic random environments
Creators: name: Hollander, Frank den
name: Santos, Renato S. dos
name: Sidoravicius, Vladas
Publisher: name: arXiv
Year: 2011
Subjects: subject: Probability (math.PR)
subject: FOS: Mathematics
subject: 60K37

description: We prove a law of large numbers for a class of $\Z^d$-valued random walks in dynamic random environments, including non-elliptic examples. We assume for the random environment a mixing property called \emph{conditional cone-mixing} and that the random walk tends to stay inside wide enough space-time cones. The proof is based on a generalization of a regeneration scheme developed by Comets and Zeitouni for static random environments and adapted by Avena, den Hollander and Redig to dynamic random environments. A number of one-dimensional examples are given. In some cases, the sign of the speed can be determined.
description: 36 pages, 4 figures
The Influence of in-medium NN cross-sections, symmetry potential and impact parameter on the isospin observables
Creators: name: Zhang, Yingxun
name: Coupland, D. D. S.
name: Danielewicz, P.
name: Li, Zhuxia
name: Liu, Hang
name: Lu, Fei
name: Lynch, W. G.
name: Tsang, M. B.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Nuclear Theory (nucl-th)
subject: Nuclear Experiment (nucl-ex)
subject: FOS: Physical sciences

description: We explore the influence of in-medium nucleon-nucleon cross section, symmetry potential and impact parameter on isospin sensitive observables in intermediate-energy heavy-ion collisions with the ImQMD05 code, a modified version of Quantum Molecular Dynamics model. At incident velocities above the Fermi velocity, we find that the density dependence of symmetry potential plays a more important role on the double neutron to proton ratio $DR(n/p)$ and the isospin transport ratio $R_i$ than the in-medium nucleon-nucleon cross sections, provided that the latter are constrained to a fixed total NN collision rate. We also explore both $DR(n/p)$ and $R_i$ as a function of the impact parameter. Since the copious production of intermediate mass fragments is a distinguishing feature of intermediate-energy heavy-ion collisions, we examine the isospin transport ratios constructed from different groups of fragments. We find that the values of the isospin transport ratios for projectile rapidity fragments with $Z\ge20$ are greater than those constructed from the entire projectile rapidity source. We believe experimental investigations of this phenomenon can be performed. These may provide significant tests of fragmentation time scales predicted by ImQMD calculations.
description: 24 pages, 9 figures, to be published in Phys. Rev. C
Superradiant energy extraction from rotating hairy Horndeski black holes
Creators: name: Jha, Sohan Kumar
name: Khodadi, Mohsen
name: Rahaman, Anisur
name: Sheykhi, Ahmad
Publisher: name: arXiv
Year: 2022
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: Adopting the manifest of low-frequency and low mass for the scalar perturbation, we perform a semi-classical analysis of the superradiance phenomenon for a rotating hairy Horndeski black hole (BH). For the spacetime under study enriched by the hairy Horndeski parameter $h$, in addition to the mass $M$ and spin $a$, we compute the amplification factor of scalar wave scattering indicating the energy extraction from the BH. We find that due to the addition of the hairy parameter $h$ in the geometry, the superradiance scattering and its frequency range enhance compared to the Kerr BH. This implies that Horndeski's gravity belongs to those alternative theories of gravity that make the amplification factor larger than the Kerr BH so that the energy extraction in its framework is more efficient than general relativity. Calculating the outgoing energy flux measured by an observer at infinity verifies the role of the hairy parameter $h$ in the increase of energy extraction efficiency from the rotating BH. By implementing the BH bomb mechanism, we present an analysis of the superradiant instability of the underlying BH spacetime against massive scalar fields. Our analysis indicates that the hairy Horndeski parameter leaves no imprint on the standard superradiant instability regime.
description: 26 pages, 3 figures, 2 tables. v3:discussion improved, Refs added, 1 table added, to be published in PRD
Coralie radial-velocity search for companions around evolved stars (CASCADES) III. A new Jupiter host-star: in-depth analysis of HD 29399 using TESS data
Creators: name: Pezzotti, C.
name: Ottoni, G.
name: Buldgen, G.
name: Lyttle, A.
name: Eggenberger, P.
name: Udry, S.
name: Ségransan, D.
name: Mayor, M.
name: Lovis, C.
name: Marmier, M.
name: Miglio, A.
name: Elsworth, Y.
name: Davies, G. R.
name: Ball, W. H.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: Context. Increasing the number of detected exoplanets is far from anecdotal, especially for long-period planets that require a long duration of observation. More detections imply a better understanding of the statistical properties of exoplanet populations, and detailed modelling of their host stars also enables thorough discussions of star-planet interactions and orbital evolution of planetary systems. Aims. In the context of the discovery of a new planetary system, we aim to perform a complete study of HD 29399 and its companion by means of radial-velocity measurements, seismic characterisation of the host-star, and modelling of the orbital evolution of the system. Methods. High-resolution spectra of HD 29399 were acquired with the CORALIE spectrograph mounted on the 1.2- m Swiss telescope located at La Silla Observatory (Chile) as part of the CASCADES survey. We used the moments of the cross-correlation function profile as well as the photometric variability of the star as diagnostics to distinguish between stellar and planetary-induced signals. To model the host star we combined forward modelling with global and local minimisation approaches and inversion techniques. We also studied the orbital history of the system under the effects of both dynamical and equilibrium tides. Results. We present the detection of a long-period giant planet. Combining these measurements with photometric observations by TESS, we are able to thoroughly model the host star and study the orbital evolution of the system. We derive stellar and planetary masses of $1.17 \pm 0.10~ M_{\odot}$ and $1.59 \pm 0.08 ~M_{Jup}$, respectively, and an age for the system of 6.2 Gyr. We show that neither dynamical nor equilibrium tides have been able to affect the orbital evolution of the planet. Moreover, no engulfment is predicted for the future evolution of the system.
Cumulant expansion in the Holstein model: Spectral functions and mobility
Creators: name: Mitrić, Petar
name: Janković, Veljko
name: Vukmirović, Nenad
name: Tanasković, Darko
Publisher: name: arXiv
Year: 2022
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: We examine the range of validity of the second-order cumulant expansion (CE) for the calculation of spectral functions, quasiparticle properties, and mobility of the Holstein polaron. We devise an efficient numerical implementation that allows us to make comparisons in a broad interval of temperature, electron-phonon coupling, and phonon frequency. For a benchmark, we use the dynamical mean-field theory (DMFT) which gives, as we have recently shown, rather accurate spectral functions in the whole parameter space, even in low dimensions. We find that in one dimension, the CE resolves well both the quasiparticle and the first satellite peak in a regime of intermediate coupling. At high temperatures, the charge mobility assumes a power law $μ\propto T^{-2}$ in the limit of weak coupling and $μ\propto T^{-3/2}$ for stronger coupling. We find that, for stronger coupling, the CE gives slightly better results than the self-consistent Migdal approximation (SCMA), while the one-shot Migdal approximation is appropriate only for a very weak electron-phonon interaction. We also analyze the atomic limit and the spectral sum rules. We derive an analytical expression for the moments in CE and find that they are exact up to the fourth order, as opposed to the SCMA where they are exact to the third order. Finally, we analyze the results in higher dimensions.
description: 22 pages, 14 figures + supp.mat. 12 pages, 9 figures
The effect of selection -- a tale of cluster mass measurement bias induced by correlation and projection
Creators: name: Zhang, Yuanyuan
name: Annis, James
Publisher: name: arXiv
Year: 2022
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: Cosmology analyses using galaxy clusters by the Dark Energy Survey have recently uncovered an issue of previously unknown selection effect affecting weak lensing mass estimates. In this letter, we use the Illustris-TNG simulation to demonstrate that selecting on galaxy counts induces a selection effect because of projection and correlation between different observables. We compute the weak-lensing-like projected mass estimations of dark matter halos and examine their projected subhalo counts. In the 2-D projected space, halos that are measured as more massive than truth have higher subhalo counts. Thus, projection along the line of sight creates cluster observables that are correlated with cluster mass measurement deviations, which in turn creates a mass measurement bias when the clusters are selected by this correlated observable. We demonstrate that the bias is predicted in a forward model using the observable-mass measurement correlation.
description: 5 pages. Comments welcomed
Measurement of D^{*\pm} Meson Production and Determination of F_2^{ccbar} at low Q2 in Deep-Inelastic Scattering at HERA
Creators: name: H1 Collaboration
Publisher: name: arXiv
Year: 2011
Subjects: subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: Inclusive production of D* mesons in deep-inelastic ep scattering at HERA is studied in the range 5 < Q^2 <100 GeV^2 of the photon virtuality and 0.02 < y < 0.7 of the inelasticity of the scattering process. The observed phase space for the D* meson is p_T(D*) > 1.25 GeV and |eta(D*)| < 1.8. The data sample corresponds to an integrated luminosity of 348 pb^{-1} collected with the H1 detector. Single and double differential cross sections are measured and the charm contribution F_2^{ccbar} to the proton structure function F_2 is determined. The results are compared to perturbative QCD predictions at next-to-leading order implementing different schemes for the charm mass treatment and with Monte Carlo models based on leading order matrix elements with parton showers.
description: 44 pages, 18 figures, new version including erratum
Eclipse Mapping of EXO 0748-676: Evidence for a Massive Neutron Star
Creators: name: Knight, Amy H.
name: Ingram, Adam
name: Middleton, Matthew
name: Drake, Jeremy
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: Determining the maximum possible neutron star (NS) mass places limits on the equation of state (EoS) of ultra-dense matter. The mass of NSs in low mass X-ray binaries can be determined from the binary mass function, providing independent constraints are placed on both the binary inclination and mass ratio. In eclipsing systems, they relate via the totality duration. EXO 0748-676 is an eclipsing NS low mass X-ray binary with a binary mass function estimated using stellar emission lines from the irradiated face of the companion. The NS mass is thus known as a function of mass ratio. Here we model the X-ray eclipses in several energy bands, utilising archival XMM-Newton data. We find a narrow region of absorbing material surrounding the companion star is required to explain the energy-dependent eclipses. Therefore, we suggest the companion may be experiencing ablation of its outer layers and that the system could transition into a redback millisecond pulsar. Our fit returns a mass ratio of $q=0.222^{+0.07}_{-0.08}$ and an inclination $i = 76.5 \pm^{1.4}_{1.1}$. Combining these with the previously measured radial velocity of $410 \pm 5$ km/s, derived from Doppler mapping analysis of H$_α$ emission during quiescence, returns a NS mass of $\sim 2 M_\odot$ even if the line originates as far from the NS as physically possible, favouring hard EoS. The inferred mass increases for a more realistic emission point. However, a $\sim 1.4 M_\odot$ canonical NS mass is possible when considering radial velocity values derived from other emission lines observed both during outburst and quiescence.
description: 21 pages, 13 Figures, accepted to MNRAS
The optimal bound on the 3-independence number obtainable from a polynomial-type method
Creators: name: Kavi, Lord C.
name: Newman, Mike
Publisher: name: arXiv
Year: 2022
Subjects: subject: Combinatorics (math.CO)
subject: FOS: Mathematics
subject: 05C50, 05C69

description: A $k$-independent set in a connected graph is a set of vertices such that any two vertices in the set are at distance greater than $k$ in the graph. The $k$-independence number of a graph, denoted $α_k$, is the size of a largest $k$-independent set in the graph. Recent results have made use of polynomials that depend on the spectrum of the graph to bound the $k$-independence number. They are optimized for the cases $k=1,2$. There are polynomials that give good (and sometimes) optimal results for general $k$, including case $k=3$. In this paper, we provide the best possible bound that can be obtained by choosing a polynomial for case $k=3$ and apply this bound to well-known families of graphs including the Hamming graph.
Detecting Human-to-Human-or-Object (H2O) Interactions with DIABOLO
Creators: name: Orcesi, Astrid
name: Audigier, Romaric
name: Toukam, Fritz Poka
name: Luvison, Bertrand
Publisher: name: arXiv
Year: 2022
Subjects: subject: Computer Vision and Pattern Recognition (cs.CV)
subject: FOS: Computer and information sciences

description: Detecting human interactions is crucial for human behavior analysis. Many methods have been proposed to deal with Human-to-Object Interaction (HOI) detection, i.e., detecting in an image which person and object interact together and classifying the type of interaction. However, Human-to-Human Interactions, such as social and violent interactions, are generally not considered in available HOI training datasets. As we think these types of interactions cannot be ignored and decorrelated from HOI when analyzing human behavior, we propose a new interaction dataset to deal with both types of human interactions: Human-to-Human-or-Object (H2O). In addition, we introduce a novel taxonomy of verbs, intended to be closer to a description of human body attitude in relation to the surrounding targets of interaction, and more independent of the environment. Unlike some existing datasets, we strive to avoid defining synonymous verbs when their use highly depends on the target type or requires a high level of semantic interpretation. As H2O dataset includes V-COCO images annotated with this new taxonomy, images obviously contain more interactions. This can be an issue for HOI detection methods whose complexity depends on the number of people, targets or interactions. Thus, we propose DIABOLO (Detecting InterActions By Only Looking Once), an efficient subject-centric single-shot method to detect all interactions in one forward pass, with constant inference time independent of image content. In addition, this multi-task network simultaneously detects all people and objects. We show how sharing a network for these tasks does not only save computation resource but also improves performance collaboratively. Finally, DIABOLO is a strong baseline for the new proposed challenge of H2O Interaction detection, as it outperforms all state-of-the-art methods when trained and evaluated on HOI dataset V-COCO.
description: ACCEPTED in IEEE International Conference on Automatic Face and Gesture Recognition (FG 2021)
Discovery of C5H+ and detection of C3H+ in TMC-1 with the QUIJOTE line survey
Creators: name: Cernicharo, J.
name: Agundez, M.
name: Cabezas, C.
name: Fuentetaja, R.
name: Tercero, B.
name: Marcelino, N.
name: Endo, Y.
name: Pardo, J. R.
name: de Vicente, P.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We report the discovery of the C5H+ cation toward TMC-1 with the QUIJOTE line survey. Four lines from J=7-6 up to J=10-9 have been identified in perfect harmonic frequency relation that can be fit with B=2411.94397 +/-0.00055 MHz and D=138+/-3 Hz. The standard deviation of the fit is 4.4 kHz. After discarding potential candidates, C5H- among them, we conclude that the carrier is C5H+, for which accurate ab initio calculations provide B=2410.3 MHz. We also report for the first time in a cold starless core the detection of the C3H+ cation. The column densities we derive for C5H+ and C3H+ are (8.8+/-0.5)e10 cm-2 and (2.4+/-0.2)e10 cm-2, respectively. Hence, the C5H+/C3H+ abundance ratio is 3.7+/-0.5. The fact that C5H+ is more abundant than C3H+ is well explained by dedicated chemical models and is due to the slow reactivity of C5H+ with H2, while C3H+ reacts with H2.
description: Accepted for publication in A&A Letters on January 5th
Hyperconvexity and Tight Span Theory for Diversities
Creators: name: Bryant, David
name: Tupper, Paul F.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Metric Geometry (math.MG)
subject: FOS: Mathematics
subject: 51F99, 92D15, 62H30, 47H10, 46A99, 54E99

description: The tight span, or injective envelope, is an elegant and useful construction that takes a metric space and returns the smallest hyperconvex space into which it can be embedded. The concept has stimulated a large body of theory and has applications to metric classification and data visualisation. Here we introduce a generalisation of metrics, called diversities, and demonstrate that the rich theory associated to metric tight spans and hyperconvexity extends to a seemingly richer theory of diversity tight spans and hyperconvexity.
description: revised in response to referee comments
Eccentric dust ring formation in Kozai-Lidov gas disks
Creators: name: Martin, Rebecca G.
name: Lubow, Stephen H.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: A highly misaligned gas disk around one component of a binary star system can undergo global Kozai-Lidov (KL) oscillations for which the disk inclination and eccentricity are exchanged. With hydrodynamical simulations of a gas and dust disk we explore the effects of these oscillations on the dust density distribution. For dust that is marginally coupled to the gas (${\rm St} \approx 1$), we find that the dust undergoes similar dynamical behaviour to the gas disk but the radial distribution of dust may be very different to the gas. The inward radial drift of the dust is faster in an eccentric disk leading to a smaller outer dust disk radius. The dust breaks into multiple narrow eccentric rings during the highly eccentric disk phase. Eccentric dust ring formation may have significant implications for the formation of planets in misaligned disks. We suggest that multiple dust rings may generally occur within gas disks that have sufficiently strong eccentricity peaks at intermediate radii.
description: Accepted for publication in ApJL
Phase diagram of holographic thermal dense QCD matter with rotation
Creators: name: Zhao, Yan-Qing
name: He, Song
name: Hou, Defu
name: Li, Li
name: Li, Zhibin
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We study the rotation effects of the hot and dense QCD matter in a non-perturbative regime by the gauge/gravity duality. We use the gravitational model that is designated to match the state-of-the-art lattice data on the thermal properties of (2+1)-flavor QCD and predict the location of the critical endpoint and the first-order phase transition line at large baryon chemical potential without rotation. After introducing the angular velocity via a local Lorentz boost, we investigate the thermodynamic quantities for the system under rotation in a self-consistent way. We find that the critical temperature and baryon chemical potential associated with the QCD phase transition decrease as the angular velocity increases. Moreover, some interesting phenomena are observed near the critical endpoint. We then construct the 3-dimensional phase diagram of the QCD matter in terms of temperature, baryon chemical potential, and angular velocity. As a parallel investigation, we also consider the gravitational model of $SU(3)$ pure gluon system, for which the 2-dimensional phase diagram associated with temperature and angular velocity has been predicted. The corresponding thermodynamic quantities with rotation are investigated.
description: 22 pages, 24 figures
Virtual injustice : technology, gendered violence and the limits of the law
Creators: name: Brydolf-Horwitz, Rachel
Publisher: name: University of British Columbia
Year: 2017

description: Technology-facilitated violence faces a dangerous combination of attitudes: that such violence isn’t serious and that it can’t be regulated. I look at linked events – the experiences and suicide of a young woman, and the passage of Canada’s first standalone anti-cyberbullying legislation – to analyze the workings of the Canadian justice system and the consequences of thinking about the digital as 'not real life.' The young woman, Rehtaeh Parsons, came to symbolize the dangers of cyberbullying, but her case involved sexual assault, the distribution of a photograph of that assault, and lengthy navigation of the justice and mental health systems in addition to the abuse directed her way via technology. In trying to understand how violence ‘online’ is naturalized and why the harms of technology-facilitated violence receive uneven recognition, I look at the roots and consequences of assumptions that orbit Rehtaeh’s case. I illustrate how as a young woman, her allegations of sexual assault were disclosed and confronted institutionally in an environment and culture steeped with longstanding discriminatory myths and stereotypes, especially around gender, alcohol, consent and sexuality. The distribution of the photograph of this traumatic night and the abuse around it were similarly invisibilized. They did not represent to the police an incident of tangible, corporeal harm because of a number of beliefs about digital technologies. In addition to the persistent partition of online and offline, with offline envisioned as ‘real life,’ I discuss how the widely used metaphor of the Internet as a frontier zone locates it on the edge of or just outside of the reach of the law. In effect, while greater attention to cyberbullying holds the promise of increasing recognition of technology-facilitated violence, there remains a disconnect between the embodied experiences of technology-facilitated violence and legal and social recognition of harm.
Dynamical mean-field theory for the Hubbard-Holstein model on a quantum device
Creators: name: Backes, Steffen
name: Murakami, Yuta
name: Sakai, Shiro
name: Arita, Ryotaro
Publisher: name: arXiv
Year: 2023
Subjects: subject: Quantum Physics (quant-ph)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: Recent developments in quantum hardware and quantum algorithms have made it possible to utilize the capabilities of current noisy intermediate-scale quantum devices for addressing problems in quantum chemistry and condensed matter physics. Here we report a demonstration of solving the dynamical mean-field theory (DMFT) impurity problem for the Hubbard-Holstein model on the IBM 27-qubit Quantum Falcon Processor Kawasaki, including self-consistency of the DMFT equations. This opens up the possibility to investigate strongly correlated electron systems coupled to bosonic degrees of freedom and impurity problems with frequency-dependent interactions. The problem involves both fermionic and bosonic degrees of freedom to be encoded on the quantum device, which we solve using a recently proposed Krylov variational quantum algorithm to obtain the impurity Green's function. We find the resulting spectral function to be in good agreement with the exact result, exhibiting both correlation and plasmonic satellites and significantly surpassing the accuracy of standard Trotter-expansion approaches. Our results provide an essential building block to study electronic correlations and plasmonic excitations on future quantum computers with modern ab initio techniques.
Semi-Analytical Solutions of Shallow Water Waves with Idealised Bottom Topographies
Creators: name: Liu, Chang
name: Clark, Antwan D.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Fluid Dynamics (physics.flu-dyn)
subject: Mathematical Physics (math-ph)
subject: Exactly Solvable and Integrable Systems (nlin.SI)
subject: FOS: Physical sciences

description: Analysing two-dimensional shallow water equations with idealised bottom topographies have many applications in the atmospheric and oceanic sciences; however, restrictive flow pattern assumptions have been made to achieve explicit solutions. This work employs the Adomian decomposition method (ADM) to develop semi-analytical formulations of these problems that preserve the direct correlation of the physical parameters while capturing the nonlinear phenomenon. Furthermore, we exploit these techniques as reverse engineering mechanisms to develop key connections between some prevalent ansatz formulations in the open literature as well as derive new families of exact solutions describing geostrophic inertial oscillations and anticyclonic vortices with finite escape times. Our semi-analytical evaluations show the promise of this approach in terms of providing robust approximations against several oceanic variations and bottom topographies while also preserving the direct correlation between the physical parameters such as the Froude number, the bottom topography, the Coriolis parameter, as well as the flow and free surface behaviours. Our numerical validations provide additional confirmations of this approach while also illustrating that ADM can also be used to provide insight and deduce novel solutions that have not been explored, which can be used to characterize various types of geophysical flows.
description: 21 pages, 3 figures