cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Allowing mobility and preventing migration? The combination of entry and stay in immigration policies
Creators: name: Lutz, Philipp
Publisher: name: Taylor & Francis
Year: 2023
Subjects: subject: Sociology
subject: FOS: Sociology
subject: Environmental Sciences not elsewhere classified
subject: Biological Sciences not elsewhere classified
subject: Science Policy
subject: Mental Health

description: Western democracies have an economic interest in admitting immigrants but at the same time they fear the political costs of doing so. A recurring idea to help reconcile this tension is to allow for temporary mobility of immigrants while restricting their permanent settlement. Trying to shed light on this matter, this article studies whether and when liberal democracies design immigration policies that prioritise (temporary) mobility over (permanent) migration. First, the underlying rationale of states for such a mobility preference is identified, before conceptualising the temporal design of immigration policies based on the combination of entry and stay regulations. Second, three theoretical explanations for the variation of countries’ mobility preference are developed: liberal constraints, institutional path-dependence and domestic politics. Third, a comparative analysis tests the arguments by studying the combination of entry and stay regulations in the immigration policies of 33 OECD countries between 1980 and 2010. The results confirm that most liberal democracies have a mobility preference in their immigration policies, but largely confined to labour migration and to a declining degree over the past decades. The temporal design of immigration policies is path-dependent on historical immigration regimes with a tendency towards a lower mobility preference the more countries become familiar with large-scale immigration.
Isomorphisms between simple modules of degenerate cyclotomic Hecke algebras
Creators: name: Rui, Hebing
name: Song, Linliang
Publisher: name: arXiv
Year: 2023
Subjects: subject: Representation Theory (math.RT)
subject: FOS: Mathematics

description: We give explicit isomorphisms between simple modules of degenerate cyclotomic Hecke algebras defined via various cellular bases. A special case gives a generalized Mullineux involution in the degenerate case.
description: 21 pages
Axion anomalies
Creators: name: Adshead, Peter
name: Lozanov, Kaloian D.
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We study fermions derivatively coupled to axion-like or pseudoscalar fields, and show that the axial vector current of the fermions is not conserved in the limit where the fermion is massless. This apparent violation of the classical chiral symmetry is due to the background axion field. We compute the contributions to this anomalous Ward identity due to the pseudoscalar field alone, which arise in Minkowski space, as well as the effects due to an interaction with an external gravitational field. For the case of massless fermions, these interactions induce terms in the axion effective action that can be removed by the addition of local counterterms. We demonstrate that these counterterms are generated by the transformation of the path integral measure when transforming the theory from a form where the chiral symmetry is manifest to one where the symmetry is only apparent after using the classical equations of motion. We work perturbatively in Minkowski space and include the effects of interactions with a linearized gravitational field. Using the heat kernel method, we study the transformation properties of the path integral measure, and include the effects of non-linear gravity as well as interactions with gauge fields. Finally, we verify our relation by considering derivatively coupled fermions during pseudoscalar-driven inflation and computing the divergence of the axial current in de Sitter spacetime.
description: 28 pages, 5 figures. Published in JHEP
Open-Closed Correspondence of K-theory and Cobordism
Creators: name: Blumenhagen, Ralph
name: Cribiori, Niccolò
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: Non-trivial K-theory groups and non-trivial cobordism groups can lead to global symmetries which are conjectured to be absent in quantum gravity. Inspired by open-closed string duality, we propose a correspondence between the two groups, which can be considered as the physical manifestation of a generalisation of the classic Conner--Floyd isomorphism. The picture is exemplified by the relations between KO-groups and Spin-cobordisms and between K-groups and Spin$^c$-cobordisms. Global symmetries related by such isomorphism are eventually gauged. By combining K-theory and cobordism, we recover then tadpole cancellation conditions in type I string theory and F-theory from a bottom-up perspective.
description: 36 pages, 2 figures, 5 tables; v2: 35 pages, 1 figure, 5 tables, substantial revision of mainly section 5
Filtered Baryogenesis
Creators: name: Baker, Michael J.
name: Breitbach, Moritz
name: Kopp, Joachim
name: Mittnacht, Lukas
name: Soreq, Yotam
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: We propose a new mechanism to simultaneously explain the observed dark matter abundance and the baryon asymmetry of the Universe. The mechanism is based on the Filtered Dark Matter scenario, where dark matter particles acquire a large mass during a first-order phase transition. This implies that only a small fraction of them are energetic enough to enter the advancing true vacuum bubbles and survive until today, while the rest are reflected and annihilate away quickly. We supplement this scenario with a CP-violating interaction, which creates a chiral asymmetry in the population of dark matter particles. In the false vacuum phase, a portal interaction quickly converts the dark sector chiral asymmetry into a Standard Model lepton asymmetry. The lepton asymmetry is then partially converted to a baryon asymmetry by standard electroweak sphaleron processes. We discuss the dependence of the generated asymmetry on the parameters of the model for two different portal interactions and demonstrate successful baryogenesis for both. For one of the portals, it is also possible to simultaneously explain the observed dark matter abundance, over many orders of magnitude in the dark matter mass.
description: 32 pages, 6 figures, 1 table; v2: mistake in the source term corrected, which leads to larger allowed parameter region in v2; added citations
Explaining the educational gradient in trust in politicians: a video-vignette survey experiment
Creators: name: Noordzij, Kjell
name: de Koster, Willem
name: van der Waal, Jeroen
Publisher: name: Taylor & Francis
Year: 2023
Subjects: subject: Neuroscience
subject: Ecology
subject: FOS: Biological sciences
subject: Biological Sciences not elsewhere classified
subject: Developmental Biology
subject: Science Policy
subject: Mental Health

description: Many liberal democracies are characterised by strong educational gradients in political trust: less-educated citizens have strikingly less trust in politicians than more-educated citizens. Informed by a wide body of research, this study tests systematically the empirical relevance of three characteristics of politicians that have been theorised as explanations for the educational gradient in trust in politicians: (1) substantive cultural stances (progressiveness/conservatism); (2) (non-)populist rhetoric; and a recently developed explanation, (3) perceived distance to citizens’ life-worlds. This study analyses data from an original, pre-registered, video-vignette survey experiment carried out among a high-quality, representative panel in the strategic case of the Netherlands, where respondents were assigned randomly to one of 16 professionally produced videos of an actor playing the role of a fictitious politician. It was found that the politician’s cultural stances and use of (non-)populist rhetoric were important drivers of the educational gradient in trust in the politician.
A Novel Image Denoising Algorithm Using Concepts of Quantum Many-Body Theory
Creators: name: Dutta, Sayantan
name: Basarab, Adrian
name: Georgeot, Bertrand
name: Kouamé, Denis
Publisher: name: arXiv
Year: 2021
Subjects: subject: Image and Video Processing (eess.IV)
subject: Computer Vision and Pattern Recognition (cs.CV)
subject: FOS: Electrical engineering, electronic engineering, information engineering
subject: FOS: Computer and information sciences

description: Sparse representation of real-life images is a very effective approach in imaging applications, such as denoising. In recent years, with the growth of computing power, data-driven strategies exploiting the redundancy within patches extracted from one or several images to increase sparsity have become more prominent. This paper presents a novel image denoising algorithm exploiting such an image-dependent basis inspired by the quantum many-body theory. Based on patch analysis, the similarity measures in a local image neighborhood are formalized through a term akin to interaction in quantum mechanics that can efficiently preserve the local structures of real images. The versatile nature of this adaptive basis extends the scope of its application to image-independent or image-dependent noise scenarios without any adjustment. We carry out a rigorous comparison with contemporary methods to demonstrate the denoising capability of the proposed algorithm regardless of the image characteristics, noise statistics and intensity. We illustrate the properties of the hyperparameters and their respective effects on the denoising performance, together with automated rules of selecting their values close to the optimal one in experimental setups with ground truth not available. Finally, we show the ability of our approach to deal with practical images denoising problems such as medical ultrasound image despeckling applications.
description: 24 pages, 14 figures; complements and expands arXiv:2108.13778
Plexcitonic quantum light emission from nanoparticle-on-mirror cavities
Creators: name: Sáez-Blázquez, R.
name: Cuartero-González, A.
name: Feist, J.
name: García-Vidal, F. J.
name: Fernández-Domínguez, A. I.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Optics (physics.optics)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We investigate the quantum-optical properties of the light emitted by a nanoparticle-on-mirror cavity filled with a single quantum emitter. Inspired by recent experiments, we model a dark-field set-up and explore the photon statistics of the scattered light under grazing laser illumination. Exploiting analytical solutions to Maxwell's equations, we quantize the nanophotonic cavity fields and describe the formation of plasmon exciton polaritons (or plexcitons) in the system. This way, we reveal that the rich plasmonic spectrum of the nanocavity offers unexplored mechanisms for nonclassical light generation that are more efficient than the resonant interaction between the emitter natural transition and the brightest optical mode. Specifically, we find three different sample configurations in which strongly antibunched light is produced. Finally, we illustrate the power of our approach by showing that the introduction of a second emitter in the platform can enhance photon correlations further.
NetKet 3: Machine Learning Toolbox for Many-Body Quantum Systems
Creators: name: Vicentini, Filippo
name: Hofmann, Damian
name: Szabó, Attila
name: Wu, Dian
name: Roth, Christopher
name: Giuliani, Clemens
name: Pescia, Gabriel
name: Nys, Jannes
name: Vargas-Calderon, Vladimir
name: Astrakhantsev, Nikita
name: Carleo, Giuseppe
Publisher: name: arXiv
Year: 2021
Subjects: subject: Quantum Physics (quant-ph)
subject: Machine Learning (cs.LG)
subject: Mathematical Software (cs.MS)
subject: Computational Physics (physics.comp-ph)
subject: FOS: Physical sciences
subject: FOS: Computer and information sciences

description: We introduce version 3 of NetKet, the machine learning toolbox for many-body quantum physics. NetKet is built around neural-network quantum states and provides efficient algorithms for their evaluation and optimization. This new version is built on top of JAX, a differentiable programming and accelerated linear algebra framework for the Python programming language. The most significant new feature is the possibility to define arbitrary neural network ansätze in pure Python code using the concise notation of machine-learning frameworks, which allows for just-in-time compilation as well as the implicit generation of gradients thanks to automatic differentiation. NetKet 3 also comes with support for GPU and TPU accelerators, advanced support for discrete symmetry groups, chunking to scale up to thousands of degrees of freedom, drivers for quantum dynamics applications, and improved modularity, allowing users to use only parts of the toolbox as a foundation for their own code.
description: 55 pages, 5 figures. Accompanying code at https://github.com/netket/netket
Dynamical and statistical properties of estimated high-dimensional ODE models: The case of the Lorenz'05 type II model
Creators: name: Pavšek, Aljaz
name: Horvat, Martin
name: Kocijan, Jus
Publisher: name: arXiv
Year: 2023
Subjects: subject: Computational Physics (physics.comp-ph)
subject: Chaotic Dynamics (nlin.CD)
subject: Data Analysis, Statistics and Probability (physics.data-an)
subject: FOS: Physical sciences

description: The performance of estimated models is often evaluated in terms of their predictive capability. In this study, we investigate another important aspect of estimated model evaluation: the disparity between the statistical and dynamical properties of estimated models and their source system. Specifically, we focus on estimated models obtained via the regression method, sparse identification of nonlinear dynamics (SINDy), one of the promising algorithms for determining equations of motion from time series of dynamical systems. We chose our data source dynamical system to be a higher-dimensional instance of the Lorenz 2005 type II model, an important meteorological toy model. We examine how the dynamical and statistical properties of the estimated models are affected by the standard deviation of white Gaussian noise added to the numerical data on which the estimated models were fitted. Our results show that the dynamical properties of the estimated models match those of the source system reasonably well within a range of data-added noise levels, where the estimated models do not generate divergent (unbounded) trajectories. Additionally, we find that the dynamics of the estimated models become increasingly less chaotic as the data-added noise level increases. We also perform a variance analysis of the (SINDy) estimated model's free parameters, revealing strong correlations between parameters belonging to the same component of the estimated model's ordinary differential equation.
description: 13 pages + refs, 10 figures
Reconciling AGN-star formation, the Soltan argument, and Meier's paradox
Creators: name: Garofalo, David
name: Kim, Matthew I.
name: Christian, Damian J.
name: Hollingworth, Emily
name: Lowery, Aaron
name: Harmon, Matthew
Publisher: name: arXiv
Year: 2015
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: We provide a theoretical context for understanding the recent work of Kalfountzou et al (2014) showing that star formation is enhanced at lower optical luminosity in radio loud quasars. Our proposal for coupling the assumption of collimated FRII quasar jet-induced star formation with lower accretion optical luminosity, also explains the observed jet power peak in active galaxies at higher redshift compared to the peak in accretion power, doing so in a way that predicts the existence of a family of radio quiet AGN associated with rapidly spinning supermassive black holes at low redshift, as mounting observations suggest. The relevance of this work lies in its promise to explain the observed cosmological evolution of accretion power, jet power, and star formation, in a way that is both compatible with the Soltan argument and resolves the so-called `Meier Paradox'.
description: 34 pages, 4 figures, accepted in ApJ
Few-mode Field Quantization for Multiple Emitters
Creators: name: Sánchez-Barquilla, Mónica
name: García-Vidal, Francisco J.
name: Fernández-Domínguez, Antonio I.
name: Feist, Johannes
Publisher: name: arXiv
Year: 2021
Subjects: subject: Optics (physics.optics)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: The control of the interaction between several quantum emitters using nanophotonic structures holds great promise for quantum technology applications. However, the theoretical description of such processes for complex nanostructures is a highly demanding task as the electromagnetic (EM) modes are in principle described by a high-dimensional continuum. We here introduce an approach that permits a quantized description of the full EM field through a "minimal" number of discrete modes. This extends the previous work in [Medina et al., Phys. Rev. Lett. 126, 093601 (2021)] to the case of an arbitrary number of emitters with arbitrary orientations, without any restrictions on the emitter level structure or dipole operators. We illustrate the power of our approach for a model system formed by three emitters placed in different positions within a metallodielectric photonic structure consisting of a metallic dimer embedded in a dielectric nanosphere. The low computational demand of this method makes it suitable for studying dynamics for a wide range of parameters. We show that excitation transfer between the emitters is highly sensitive to the properties of the hybrid photonic-plasmonic modes, demonstrating the potential of such structures for achieving control over emitter interactions.
Not the mode of allocation but refugees’ right to work drives European citizens’ preferences on refugee policy
Creators: name: Letki, Natalia
name: Walentek, Dawid
name: Dinesen, Peter Thisted
name: Liebe, Ulf
Publisher: name: Taylor & Francis
Year: 2023
Subjects: subject: Medicine
subject: Genetics
subject: FOS: Biological sciences
subject: Sociology
subject: FOS: Sociology
subject: Information Systems not elsewhere classified
subject: Cancer
subject: Science Policy
subject: Mental Health
subject: Infectious Diseases
subject: FOS: Health sciences

description: Europe remains a destination of an ongoing influx of asylum seekers. The attempts to build an EU-wide political consensus around refugee policy have so far failed. This article provides a perspective on EU citizens’ preferred policy towards refugees and asylum seekers at both the EU and domestic levels. A hidden policy consensus is identified in which European citizens across all social and ideological backgrounds prefer refugees to have the right to work but their freedom of movement to be restricted while their application for asylum is being processed. At the same time, the mode of refugee allocation between countries, which has been prominent in political debates across Europe, is relatively unimportant to respondents, as they focus on the domestic level rather than EU-level policy. The widespread consensus on support for refugees’ participation in the labour market may unite EU citizens around cautious hospitality by deemphasising allocation principles, and stressing country-level solutions.
Hot subdwarf stars and their connection to thermonuclear supernovae
Creators: name: Geier, S.
name: Kupfer, T.
name: Ziegerer, E.
name: Heber, U.
name: Nemeth, P.
name: Irrgang, A.
name: team, MUCHFUSS
Publisher: name: arXiv
Year: 2016
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: Hot subdwarf stars (sdO/Bs) are evolved core helium-burning stars with very thin hydrogen envelopes, which can be formed by common envelope ejection. Close sdB binaries with massive white dwarf (WD) companions are potential progenitors of thermonuclear supernovae type Ia (SN Ia). We discovered such a progenitor candidate as well as a candidate for a surviving companion star, which escapes from the Galaxy. More candidates for both types of objects have been found by crossmatching known sdB stars with proper motion and light curve catalogues. The Gaia mission will provide accurate astrometry and light curves of all the stars in our hot subdwarf sample and will allow us to compile a much larger all-sky catalogue of those stars. In this way we expect to find hundreds of progenitor binaries and ejected companions.
description: Proceedings of the 11th Pacific Rim Conference on Stellar Astrophysics, Hong Kong 2015, Journal of Physics: Conference Series, in press
What makes people trust or distrust politicians? Insights from open-ended survey questions
Creators: name: Winsvold, Marte
name: Haugsgjerd, Atle
name: Saglie, Jo
name: Segaard, Signe Bock
Publisher: name: Taylor & Francis
Year: 2023
Subjects: subject: Biotechnology
subject: Sociology
subject: FOS: Sociology
subject: Developmental Biology
subject: Cancer
subject: Science Policy
subject: Mental Health

description: High political trust is often interpreted as a sign of good democratic health, and widespread distrust as a sign of democratic ill health. However, there is little knowledge about the basis on which people make assessments about whether to trust or distrust political actors. This article develops and applies a typology for political trust judgement. Through a content analysis of 1,105 open-ended survey questions about political trust and distrust, the study finds that people tend to assess (dis)trust of politicians based on whether they see the politicians as predictable, intrinsically committed, competent and responsive. Moreover, the study finds that citizens use different judgement bases to describe trust and distrust, suggesting that the two concepts are not pure negations of each other. While predictability is the most frequently reported basis for trusting politicians, a lack of intrinsic commitment is the most frequently reported basis for distrusting politicians. This article discusses the reasons for and implications of the apparently different bases for weighing judgements on trust and distrust.
The interaction of multiple bubbles in a Hele-Shaw channel
Creators: name: Keeler, J. S.
name: Gaillard, A.
name: Lawless, J.
name: Thompson, A. B.
name: Juel, A.
name: Hazel, A.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Fluid Dynamics (physics.flu-dyn)
subject: FOS: Physical sciences

description: We study the dynamics of two air bubbles driven by the motion of a suspending viscous fluid in a Hele-Shaw channel with a small elevation along its centreline via physical experiment and numerical simulation of a depth-averaged model. For a single-bubble system we establish that, in general, bubble propagation speed monotonically increases with bubble volume so that two bubbles of different sizes, in the absence of any hydrodynamic interactions will either coalesce or separate in a finite time. However our experiments indicate that the bubbles interact and that an unstable two-bubble state is responsible for the eventual dynamical outcome: coalescence or separation. These results motivate us to develop an edge-tracking routine and calculate these weakly unstable two-bubble steady states from the governing equations. The steady states consist of pairs of `aligned' bubbles that appear on the same side of the centreline with the larger bubble leading. We also discover, through time-simulations and physical experiment, another class of two-bubble states which, surprisingly, consist of stable two-bubble steady states. In contrast to the `aligned' steady states, these bubbles appear either side of the centreline and are `offset' from each other. We calculate the bifurcation structures of both classes of steady states as the flow-rate and bubble volume ratio is varied. We find that they exhibit intriguing similarities to the single-bubble bifurcation structure, which has implications for the existence of $n$-bubble steady states.
description: 17 pages
Active region filaments might harbor weak magnetic fields
Creators: name: Baso, C. J. Díaz
name: González, M. J. Martínez
name: Ramos, A. Asensio
Publisher: name: arXiv
Year: 2016
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: Recent spectropolarimetric observations of active region filaments have revealed polarization profiles with signatures typical of the strong field Zeeman regime. The conspicuous absence in those observations of scattering polarization and Hanle effect signatures was then pointed out by some authors. This was interpreted either as a signature of mixed "turbulent" field components or as a result of optical thickness. In this article, we present a natural scenario to explain these Zeeman-only spectro-polarimetric observations of active region filaments. We propose a two-component model, one on top of the other. Both components have horizontal fields, the azimuth difference between them being close to 90 degrees. The component that lies lower in the atmosphere is permeated by a strong field of the order of 600 G, while the upper component has much weaker fields, of the order of 10 G. The ensuing scattering polarization signatures of the individual components have opposite signs, so that its combination along the line of sight reduces --and even can cancel out-- the Hanle signatures, giving rise to an apparent only-Zeeman profile. This model is also applicable to other chromospheric structures seen in absorption above active regions.
description: 6 pages, 1 figure. Accepted by ApJ
Weak-strong uniqueness for the Navier-Stokes equation for two fluids with ninety degree contact angle and same viscosities
Creators: name: Hensel, Sebastian
name: Marveggio, Alice
Publisher: name: arXiv
Year: 2021
Subjects: subject: Analysis of PDEs (math.AP)
subject: FOS: Mathematics

description: We consider the flow of two viscous and incompressible fluids within a bounded domain modeled by means of a two-phase Navier-Stokes system. The two fluids are assumed to be immiscible, meaning that they are separated by an interface. With respect to the motion of the interface, we consider pure transport by the fluid flow. Along the boundary of the domain, a complete slip boundary condition for the fluid velocities and a constant ninety degree contact angle condition for the interface are assumed. The main result of the present work establishes in 2D a weak-strong uniqueness result in terms of a varifold solution concept à la Abels (Interfaces Free Bound. 9, 2007). The proof is based on a relative entropy argument. More precisely, we extend ideas from the recent work of Fischer and the first author (Arch. Ration. Mech. Anal. 236, 2020) to incorporate the contact angle condition. To focus on the effects of the necessarily singular geometry, we work for simplicity in the regime of same viscosities for the two fluids.
description: 63 pages
Sign learning kink-based (SiLK) quantum Monte Carlo for molecular systems
Creators: name: Ma, Xiaoyao
name: Hall, Randall W.
name: Loffler, Frank
name: Kowalski, Karol
name: Bhaskaran-Nair, Kiran
name: Jarrell, Mark
name: Moreno, Juana
Publisher: name: arXiv
Year: 2015
Subjects: subject: Computational Physics (physics.comp-ph)
subject: Chemical Physics (physics.chem-ph)
subject: FOS: Physical sciences

description: The Sign Learning Kink (SiLK) based Quantum Monte Carlo (QMC) method is used to calculate the ab initio ground state energies for multiple geometries of the H$_{2}$O, N$_2$, and F$_2$ molecules. The method is based on Feynman's path integral formulation of quantum mechanics and has two stages. The first stage is called the learning stage and reduces the well-known QMC minus sign problem by optimizing the linear combinations of Slater determinants which are used in the second stage, a conventional QMC simulation. The method is tested using different vector spaces and compared to the results of other quantum chemical methods and to exact diagonalization. Our findings demonstrate that the SiLK method is accurate and reduces or eliminates the minus sign problem.
description: 20 pages, 9 figures, to appear in the Journal of Chemical Physics
Events in quantum mechanics are maximally non-absolute
Creators: name: Moreno, George
name: Nery, Ranieri
name: Duarte, Cristhiano
name: Chaves, Rafael
Publisher: name: arXiv
Year: 2021
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: The notorious quantum measurement problem brings out the difficulty to reconcile two quantum postulates: the unitary evolution of closed quantum systems and the wave-function collapse after a measurement. This problematics is particularly highlighted in the Wigner's friend thought experiment, where the mismatch between unitary evolution and measurement collapse leads to conflicting quantum descriptions for different observers. A recent no-go theorem has established that the (quantum) statistics arising from an extended Wigner's friend scenario is incompatible when one try to hold together three innocuous assumptions, namely no-superdeterminism, parameter independence and absoluteness of observed events. Building on this extended scenario, we introduce two novel measures of non-absoluteness of events. The first is based on the EPR2 decomposition, and the second involves the relaxation of the absoluteness hypothesis assumed in the aforementioned no-go theorem. To prove that quantum correlations can be maximally non-absolute according to both quantifiers, we show that chained Bell inequalities (and relaxations thereof) are also valid constraints for Wigner's experiment.
The non-abelian tensor square of residually finite groups
Creators: name: Bastos, Raimundo
name: Rocco, Noraí Romeu
Publisher: name: arXiv
Year: 2016
Subjects: subject: Group Theory (math.GR)
subject: FOS: Mathematics
subject: 20F45, 20E26, 20F40

description: Let $m,n$ be positive integers and $p$ a prime. We denote by $ν(G)$ an extension of the non-abelian tensor square $G \otimes G$ by $G \times G$. We prove that if $G$ is a residually finite group satisfying some non-trivial identity $f \equiv~1$ and for every $x,y \in G$ there exists a $p$-power $q=q(x,y)$ such that $[x,y^φ]^q = 1$, then the derived subgroup $ν(G)'$ is locally finite (Theorem A). Moreover, we show that if $G$ is a residually finite group in which for every $x,y \in G$ there exists a $p$-power $q=q(x,y)$ dividing $p^m$ such that $[x,y^φ]^q$ is left $n$-Engel, then the non-abelian tensor square $G \otimes G$ is locally virtually nilpotent (Theorem B).
description: 11 pages. arXiv admin note: substantial text overlap with arXiv:1505.04468
One-Dimensional Sectors From the Squashed Three-Sphere
Creators: name: Bomans, Pieter
name: Pufu, Silviu
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: Three-dimensional $\mathcal{N} = 4$ superconformal field theories contain 1d topological sectors consisting of twisted linear combinations of half-BPS local operators that can be inserted anywhere along a line. After a conformal mapping to a round three-sphere, the 1d sectors are now defined on a great circle of $S^3$. We show that the 1d topological sectors are preserved under the squashing of the sphere. For gauge theories with matter hypermultiplets, we use supersymmetric localization to derive an explicit description of the topological sector associated with the Higgs branch. Furthermore, we find that the dependence of the 1d correlation functions on the squashing parameter $b$ can be removed after appropriate rescalings. One can introduce real mass and Fayet-Iliopolous parameters that, after appropriate rescalings, modify the 1d theory on the squashed sphere precisely as they do on the round sphere. In addition, we also show that when a generic 3d $\mathcal{N}=4$ theory is deformed by real mass parameters, this deformation translates into a universal deformation of the corresponding 1d theory.
description: 42+20 pages
Neutrinoless double beta decay in the minimal type-I seesaw model: How the enhancement or cancellation happens?
Creators: name: Fang, Dong-Liang
name: Li, Yu-Feng
name: Zhang, Yi-Yu
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: We discuss the contribution of right-handed neutrinos (RHNs) to the effective neutrino mass of the neutrinoless double beta decay within the minimal type-I seesaw model using the intrinsic seesaw relation of neutrino mass and mixing parameters and the relative mass dependence of the nuclear matrix elements. In the viable parameter space, we find the possibilities of both the enhancement and cancellation to the effective neutrino mass from RHNs. The bounds on the parameter space of the RHNs can be determined with the effective neutrino mass extracted from neutrinoless double beta decay experiments.
description: 15 pages, 6 figures, PLB published version
MarS3D: A Plug-and-Play Motion-Aware Model for Semantic Segmentation on Multi-Scan 3D Point Clouds
Creators: name: Liu, Jiahui
name: Chang, Chirui
name: Liu, Jianhui
name: Wu, Xiaoyang
name: Ma, Lan
name: Qi, Xiaojuan
Publisher: name: arXiv
Year: 2023
Subjects: subject: Computer Vision and Pattern Recognition (cs.CV)
subject: FOS: Computer and information sciences

description: 3D semantic segmentation on multi-scan large-scale point clouds plays an important role in autonomous systems. Unlike the single-scan-based semantic segmentation task, this task requires distinguishing the motion states of points in addition to their semantic categories. However, methods designed for single-scan-based segmentation tasks perform poorly on the multi-scan task due to the lacking of an effective way to integrate temporal information. We propose MarS3D, a plug-and-play motion-aware module for semantic segmentation on multi-scan 3D point clouds. This module can be flexibly combined with single-scan models to allow them to have multi-scan perception abilities. The model encompasses two key designs: the Cross-Frame Feature Embedding module for enriching representation learning and the Motion-Aware Feature Learning module for enhancing motion awareness. Extensive experiments show that MarS3D can improve the performance of the baseline model by a large margin. The code is available at https://github.com/CVMI-Lab/MarS3D.
Inversion of Stokes Profiles with Systematic Effects
Creators: name: Ramos, A. Asensio
name: Rodriguez, J. de la Cruz
name: Gonzalez, M. J. Martinez
name: Yabar, A. Pastor
Publisher: name: arXiv
Year: 2016
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: Quantitative thermodynamical, dynamical and magnetic properties of the solar and stellar plasmas are obtained by interpreting their emergent non-polarized and polarized spectrum. This inference requires the selection of a set of spectral lines particularly sensitive to the physical conditions in the plasma and a suitable parametric model of the solar/stellar atmosphere. Nonlinear inversion codes are then used to fit the model to the observations. However, the presence of systematic effects like nearby or blended spectral lines, telluric absorption or incorrect correction of the continuum, among others, can strongly affect the results. We present an extension to current inversion codes that can deal with these effects in a transparent way. The resulting algorithm is very simple and can be applied to any existing inversion code with the addition of a few lines of code as an extra step in each iteration.
description: 11 pages, 5 figures, accepted for publication in A&A
Thermodynamics and phase transition of BTZ black hole in a cavity
Creators: name: Huang, Yuchen
name: Tao, Jun
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: In this paper, we study the thermodynamics and phase transition of a BTZ black hole in a finite space region, namely a cavity. By imposing a temperature-fixed boundary condition on the wall of the cavity and evaluating the Euclidean action, we derive the thermodynamic quantities and then construct the first law of thermodynamics for a static and neutral BTZ black hole, a rotating BTZ black hole and a charged BTZ black hole, respectively. We prove that heat capacities of these three types of black holes are always non-negative. Considering a grand canonical ensemble, we find that the non-extreme rotating black hole and the charged black hole are locally thermodynamically stable by calculating the Hessian matrix of their internal energy. At the phase transition level, it shows that for the static and neutral BTZ black hole, the phase transition only exists between thermal AdS3 spacetime and the black hole. The temperature where the phase transition occurs is only determined by the cavity radius. For rotating and charged cases, there may exist an extra second-order phase transition between the black hole and the black hole-cavity merger state. The phase structure of a BTZ black hole in a cavity shows strong dissimilarities from that without the cavity.
description: 28 pages, 8 figures, to be published in Nuclear Physics B
Chaotic dynamics of small sized charged Yukawa Dust Clusters
Creators: name: Deshwal, Priya
name: Yadav, Mamta
name: Prasad, Chaitanya
name: Sridev, Shantam
name: Ahuja, Yash
name: Maity, Srimanta
name: Das, Amita
Publisher: name: arXiv
Year: 2021
Subjects: subject: Plasma Physics (physics.plasm-ph)
subject: FOS: Physical sciences

description: In a recent work, [1] the equilibrium of a cluster of charged dust particles mutually interacting with screened Coulomb force and radially confined by an externally applied electric field in a 2-D configuration was studied. It was shown that the particles arranged themselves on discrete radial rings forming a lattice structure. In some cases with the specific number of particles, no static equilibrium was observed; instead, angular rotation of particles positioned at various rings was observed. In a two-ringed structure, it was shown that the direction of rotation was opposite. The direction of rotation was also observed to change apparently at random time intervals. A detailed characterization of the dynamics of small-sized Yukawa clusters has been carried out in the present work. In particular, it has been shown that the dynamical time reversal of angular rotation exhibits chaotic behavior.
description: 7 pages, 9 figures
Company2Vec -- German Company Embeddings based on Corporate Websites
Creators: name: Gerling, Christopher
Publisher: name: arXiv
Year: 2023
Subjects: subject: Artificial Intelligence (cs.AI)
subject: Computational Finance (q-fin.CP)
subject: Portfolio Management (q-fin.PM)
subject: FOS: Computer and information sciences
subject: FOS: Economics and business

description: With Company2Vec, the paper proposes a novel application in representation learning. The model analyzes business activities from unstructured company website data using Word2Vec and dimensionality reduction. Company2Vec maintains semantic language structures and thus creates efficient company embeddings in fine-granular industries. These semantic embeddings can be used for various applications in banking. Direct relations between companies and words allow semantic business analytics (e.g. top-n words for a company). Furthermore, industry prediction is presented as a supervised learning application and evaluation method. The vectorized structure of the embeddings allows measuring companies similarities with the cosine distance. Company2Vec hence offers a more fine-grained comparison of companies than the standard industry labels (NACE). This property is relevant for unsupervised learning tasks, such as clustering. An alternative industry segmentation is shown with k-means clustering on the company embeddings. Finally, this paper proposes three algorithms for (1) firm-centric, (2) industry-centric and (3) portfolio-centric peer-firm identification.
description: Accepted for Publication in: International Journal of Information Technology & Decision Making (2023)
Pauli Spin Blockade in a Resonant Triple Quantum Dot Molecule
Creators: name: Shim, Yun-Pil
Publisher: name: arXiv
Year: 2021
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Pauli spin blockade in quantum dot systems occurs when the charge transport is allowed only for some spin states, and it has been an efficient tool in spin-based qubit devices in semiconductors. We theoretically investigate a Pauli spin blockade in a triple quantum dot molecule consisting of three identical quantum dots in a semiconductor in the presence of an external magnetic field through the molecule. When the three-electron state is on resonance with two- or four-electron states, the Aharonov-Bohm oscillation and the Zeeman splitting lead to a periodic spin blockade effect. We focus on the spin blockade at a two- and three-electron resonance, and show that we can tune the magnetic field to selectively allow only spin-singlet or spin-triplet state to add an additional electron from tunnel-coupled leads. This spin blockade maintains the three quantum dots at the optimal sweet spot against the charge noise, demonstrating its potential as an efficient readout scheme for the qubits in quantum dot systems.
On Extraction of Twist-Two Compton Form Factors from DVCS Observables Through Harmonic Analysis
Creators: name: Shiells, Kyle
name: Guo, Yuxun
name: Ji, Xiangdong
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We investigate the exercise of locally extracting the real and imaginary parts of the four twist-2 Compton form factors (CFFs) $\{\mathcal{H},\mathcal{E},\widetilde{\mathcal{H}},\widetilde{\mathcal{E}}\}$ which arise in the deeply virtual Compton scattering (DVCS) process $e + p \rightarrow e + p + γ$. Neglecting dynamical higher-twist contributions, we find that there are a sufficient number of DVCS observables and degrees of freedom to extract all 8 leading quantities model-independently, exploiting the azimuthal dependence of the absolute cross sections across all possible beam and target polarizations at a common kinematical point in $\{Q,t,x_B,y\}$. As an example, for typical JLab lab-frame kinematics, we simplify the reduced DVCS observables to their dominant terms, providing a sufficient number of equations for local determination of the twist-2 CFFs. We demonstrate the feasibility using harmonic fitting to both cross sections and beam spin asymmetries with both real and pseudo-data.
description: 52 pages, 8 figures, 5 tables
Two-dimensional superconductivity at the surfaces of KTaO3 gated with ionic liquid
Creators: name: Ren, Tianshuang
name: Li, Miaocong
name: Sun, Xikang
name: Ju, Lele
name: Liu, Yuan
name: Hong, Siyuan
name: Sun, Yanqiu
name: Tao, Qian
name: Zhou, Yi
name: Xu, Zhu-An
name: Xie, Yanwu
Publisher: name: arXiv
Year: 2022
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: The recent observation of superconductivity at the interfaces between KTaO3 and EuO (or LaAlO3) offers a new example of emergent phenomena at oxide interfaces. This superconductivity exhibits an unusual strong dependence on the crystalline orientation of KTaO3 and its superconducting transition temperature Tc is nearly one order of magnitude higher than that of the seminal LaAlO3/SrTiO3 interface. To understand its mechanism, it is crucial to address if the formation of oxide interfaces is indispensable for the presence of superconductivity. Here, by exploiting ionic liquid (IL) gating, we obtain superconductivity at KTaO3 (111) and (110) surfaces with Tc up to 2.0 K and 1.0 K, respectively. This oxide-interface-free superconductivity gives a clear experimental evidence that the essential physics of KTaO3 interface superconductivity lies in the KTaO3 surfaces doped with electrons. Moreover, the ability to control superconductivity at surfaces with IL provides a simple way to study the intrinsic superconductivity in KTaO3.
description: 14 pages in total. 4 figures in the maix text. 6 figures in the Suppemental Materials
Efficient representation of head-related transfer functions in continuous space-frequency domains
Creators: name: Szwajcowski, Adam
Publisher: name: arXiv
Year: 2023
Subjects: subject: Audio and Speech Processing (eess.AS)
subject: Sound (cs.SD)
subject: FOS: Electrical engineering, electronic engineering, information engineering
subject: FOS: Computer and information sciences

description: Utilizing spherical harmonic (SH) domain has been established as the default method of obtaining continuity over space in head-related transfer functions (HRTFs). This paper concerns different variants of extending this solution by replacing SHs with four-dimensional (4D) continuous functional models in which frequency is imagined as another physical dimension. Recently developed hyperspherical harmonic (HSH) representation is compared with models defined in spherindrical coordinate system by merging SHs with one-dimensional basis functions. The efficiency of both approaches is evaluated based on the reproduction errors for individual HRTFs from HUTUBS database, including detailed analysis of its dependency on chosen orders of approximation in frequency and space. Employing continuous functional models defined in 4D coordinate systems allows HRTF magnitude spectra to be expressed as a small set of coefficients which can be decoded back into values at any direction and frequency. The best performance was noted for HSHs and SHs merged with reverse Fourier-Bessel series, with the former featuring better compression abilities, achieving slightly higher accuracy for low number of coefficients. The presented models can serve multiple purposes, such as interpolation, compression or parametrization for machine learning applications, and can be applied not only to HRTFs but also to other types of directivity functions, e.g. sound source directivity.
description: 33 pages, 9 figures, preprint of published paper submitted for green open access to fulfill funding institution mandate
Chaos in Celestial CFT
Creators: name: Pasterski, Sabrina
name: Verlinde, Herman
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: Celestial holography proposes a duality between gravitational scattering in asymptotically flat space-time and a conformal field theory living on the celestial sphere. Its dictionary relates the infinite dimensional space-time symmetry group to Ward identities of the CFT. The spontaneous breaking of these asymptotic symmetries governs the dynamics of the soft sector in the CFT. Here we show that this sector encodes non-trivial backreaction effects that exhibit characteristics of maximal quantum chaos. A key element in the derivation is the identification of the Hilbert space of celestial CFT, defined through radial quantization, with that of a constantly accelerating Rindler observer. From the point of view of the bulk, Rindler particles exhibit Lyapunov behavior due to shockwave interactions that shift the observer horizon. From the point of view of the boundary, the superrotation Goldstone modes affect the relevant representations of the celestial Virasoro symmetry in a manner that induces Lyapunov behavior of out-of-time-ordered celestial correlators.
description: 29 pages, 6 figures