cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Protection of entanglement between two two-level atoms
Creators: name: Zhang, Anwei
Publisher: name: arXiv
Year: 2016
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: The dynamical evolution of entanglement between two polarizable two-level atoms in weak interaction with electromagnetic vacuum fluctuations is investigated. We find that, for initial Bell state $ψ^{\pm}$, the decay rate of entanglement between atoms is just the superradiant spontaneous emission rate, which depends not only on the spontaneous emission rate of atom but also on the modulation of the spontaneous emission rate due to the presence of another atom. It is shown that, with the presence of a boundary, the entanglement between transversely polarizable atoms can be protected for a very long time. It is pointed out that when the two atoms in initial Bell state $ψ^{-}$ are put close enough , the entanglement between them can also be protected.
description: 11pages,3figure. Accepted by Laser Physics Letters
Efficient anchor loss suppression in coupled near-field optomechanical resonators
Creators: name: Luiz, Gustavo O.
name: Santos, Felipe G. S.
name: Benevides, Rodrigo S.
name: Espinel, Yovanny A. V.
name: Alegre, Thiago P. M.
name: Wiederhecker, Gustavo S.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: Elastic dissipation through radiation towards the substrate is a major loss channel in micro- and nanomechanical resonators. Engineering the coupling of these resonators with optical cavities further complicates and constrains the design of low-loss optomechanical devices. In this work we rely on the coherent cancellation of mechanical radiation to demonstrate material and surface absorption limited silicon near-field optomechanical resonators oscillating at tens of MHz. The effectiveness of our dissipation suppression scheme is investigated at room and cryogenic temperatures. While at room temperature we can reach a maximum quality factor of 7.61k ($fQ$-product of the order of $10^{11}$~Hz), at 22~K the quality factor increases to 37k, resulting in a $fQ$-product of $2\times10^{12}$~Hz.
Testing GitHub projects on custom resources using unprivileged Kubernetes runners
Creators: name: Sfiligoi, Igor
name: McDonald, Daniel
name: Knight, Rob
name: Würthwein, Frank
Publisher: name: arXiv
Year: 2023
Subjects: subject: Software Engineering (cs.SE)
subject: FOS: Computer and information sciences

description: GitHub is a popular repository for hosting software projects, both due to ease of use and the seamless integration with its testing environment. Native GitHub Actions make it easy for software developers to validate new commits and have confidence that new code does not introduce major bugs. The freely available test environments are limited to only a few popular setups but can be extended with custom Action Runners. Our team had access to a Kubernetes cluster with GPU accelerators, so we explored the feasibility of automatically deploying GPU-providing runners there. All available Kubernetes-based setups, however, require cluster-admin level privileges. To address this problem, we developed a simple custom setup that operates in a completely unprivileged manner. In this paper we provide a summary description of the setup and our experience using it in the context of two Knight lab projects on the Prototype National Research Platform system.
description: 5 pages, 1 figure, To be published in proceedings of PEARC23
Revisiting Unsupervised Learning for Defect Prediction
Creators: name: Fu, Wei
name: Menzies, Tim
Publisher: name: arXiv
Year: 2017
Subjects: subject: Software Engineering (cs.SE)
subject: Machine Learning (cs.LG)
subject: FOS: Computer and information sciences

description: Collecting quality data from software projects can be time-consuming and expensive. Hence, some researchers explore "unsupervised" approaches to quality prediction that does not require labelled data. An alternate technique is to use "supervised" approaches that learn models from project data labelled with, say, "defective" or "not-defective". Most researchers use these supervised models since, it is argued, they can exploit more knowledge of the projects. At FSE'16, Yang et al. reported startling results where unsupervised defect predictors outperformed supervised predictors for effort-aware just-in-time defect prediction. If confirmed, these results would lead to a dramatic simplification of a seemingly complex task (data mining) that is widely explored in the software engineering literature. This paper repeats and refutes those results as follows. (1) There is much variability in the efficacy of the Yang et al. predictors so even with their approach, some supervised data is required to prune weaker predictors away. (2)Their findings were grouped across $N$ projects. When we repeat their analysis on a project-by-project basis, supervised predictors are seen to work better. Even though this paper rejects the specific conclusions of Yang et al., we still endorse their general goal. In our our experiments, supervised predictors did not perform outstandingly better than unsupervised ones for effort-aware just-in-time defect prediction. Hence, they may indeed be some combination of unsupervised learners to achieve comparable performance to supervised ones. We therefore encourage others to work in this promising area.
description: 11 pages, 5 figures. Accepted at FSE2017
Numerical binary black hole mergers in dynamical Chern-Simons: I. Scalar field
Creators: name: Okounkova, Maria
name: Stein, Leo C.
name: Scheel, Mark A.
name: Hemberger, Daniel A.
Publisher: name: arXiv
Year: 2017
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: Testing general relativity in the non-linear, dynamical, strong-field regime of gravity is one of the major goals of gravitational wave astrophysics. Performing precision tests of general relativity (GR) requires numerical inspiral, merger, and ringdown waveforms for binary black hole (BBH) systems in theories beyond GR. Currently, GR and scalar-tensor gravity are the only theories amenable to numerical simulations. In this article, we present a well-posed perturbation scheme for numerically integrating beyond-GR theories that have a continuous limit to GR. We demonstrate this scheme by simulating BBH mergers in dynamical Chern-Simons gravity (dCS), to linear order in the perturbation parameter. We present mode waveforms and energy fluxes of the dCS pseudoscalar field from our numerical simulations. We find good agreement with analytic predictions at early times, including the absence of pseudoscalar dipole radiation. We discover new phenomenology only accessible through numerics: a burst of dipole radiation during merger. We also quantify the self-consistency of the perturbation scheme. Finally, we estimate bounds that GR-consistent LIGO detections could place on the new dCS length scale, approximately $\ell \lesssim \mathcal{O}(10)~\mathrm{km}$.
description: 14+4 pages, 8 figures, 1 table; visualization available at http://www.youtube.com/watch?v=WQH-1b_XUM4 . Matches published version
Quantum Backreaction on Classical Dynamics
Creators: name: Vachaspati, Tanmay
Publisher: name: arXiv
Year: 2017
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Motivated by various systems in which quantum effects occur in classical backgrounds, we consider the dynamics of a classical particle as described by a coherent state that is coupled to a quantum bath via bi-quadratic interactions. We evaluate the resulting quantum dissipation of the motion of the classical particle. We also find classical initial conditions for the bath that effectively lead to the same dissipation as that due to quantum effects, possibly providing a way to approximately account for quantum backreaction within a classical analysis.
description: 8 pages; fixed minor typos
Defining a canonical unit for accounting purposes
Creators: name: Andrijauskas, Fabio
name: Sfiligoi, Igor
name: Würthwein, Frank
Publisher: name: arXiv
Year: 2023
Subjects: subject: Distributed, Parallel, and Cluster Computing (cs.DC)
subject: FOS: Computer and information sciences

description: Compute resource providers often put in place batch compute systems to maximize the utilization of such resources. However, compute nodes in such clusters, both physical and logical, contain several complementary resources, with notable examples being CPUs, GPUs, memory and ephemeral storage. User jobs will typically require more than one such resource, resulting in co-scheduling trade-offs of partial nodes, especially in multi-user environments. When accounting for either user billing or scheduling overhead, it is thus important to consider all such resources together. We thus define the concept of a threshold-based "canonical unit" that combines several resource types into a single discrete unit and use it to characterize scheduling overhead and make resource billing more fair for both resource providers and users. Note that the exact definition of a canonical unit is not prescribed and may change between resource providers. Nevertheless, we provide a template and two example definitions that we consider appropriate in the context of the Open Science Grid.
description: 6 pages, 2 figures, To be published in proceedings of PEARC23
Photoproduction of the $B_c^{(*)}$ Meson at the LHeC
Creators: name: Huan-Yu, Bi
name: Ren-You, Zhang
name: Han, Hua-Yong
name: Yi, Jiang
name: Wu, Xing-Gang
Publisher: name: arXiv
Year: 2016
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We make a detailed study on the photoproduction mechanism of the doubly heavy flavored $B_c^{(*)}$ meson at the purposed Large Hadron Electron Collider (LHeC) within the framework of nonrelativistic QCD. In addition to the photoproduction mechanism via the gluon-induced channel $γ+ g \to B_c^{(*)} + b + \bar{c}$, the extrinsic heavy quark mechanism via the two channels $γ+ c \to B_c^{(*)} + b $ and $γ+ \bar{b} \to B_c^{(*)} + \bar{c}$ has also been studied. Those two extrinsic channels are generally suppressed by the heavy quark distribution functions in proton, which however provide significant contributions in low and intermediate $p_T$ region. A detailed comparison of those channels together with the theoretical uncertainties has been presented. By summing up all the mentioned photoproduction channels, we observe that about $(1.04^{+0.90}_{-0.53})\times 10^{5}$ $B_c$ and $(4.86^{+3.72}_{-2.30})\times 10^{5}$ $B_c^*$ events can be generated at the LHeC in one operation year with the proton-electron collision energy $\sqrt{S}=1.30$ TeV and the luminosity ${\mathcal L}\simeq 10^{33}$ ${\rm cm}^{-2} {\rm s}^{-1}$. Here the errors are for $m_c=1.50\pm0.20$ GeV and $m_b=4.9\pm0.40$ GeV. Thus, in addition to the hadronic experiments, the LHeC shall provide another helpful platform for studying the $B_c^{(*)}$ meson properties, especially to test the extrinsic heavy quark mechanism.
Optimization and Portability of a Fusion OpenACC-based FORTRAN HPC Code from NVIDIA to AMD GPUs
Creators: name: Sfiligoi, Igor
name: Belli, Emily A.
name: Candy, Jeff
name: Budiardja, Reuben D.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Distributed, Parallel, and Cluster Computing (cs.DC)
subject: Performance (cs.PF)
subject: Plasma Physics (physics.plasm-ph)
subject: FOS: Computer and information sciences
subject: FOS: Physical sciences

description: NVIDIA has been the main provider of GPU hardware in HPC systems for over a decade. Most applications that benefit from GPUs have thus been developed and optimized for the NVIDIA software stack. Recent exascale HPC systems are, however, introducing GPUs from other vendors, e.g. with the AMD GPU-based OLCF Frontier system just becoming available. AMD GPUs cannot be directly accessed using the NVIDIA software stack, and require a porting effort by the application developers. This paper provides an overview of our experience porting and optimizing the CGYRO code, a widely-used fusion simulation tool based on FORTRAN with OpenACC-based GPU acceleration. While the porting from the NVIDIA compilers was relatively straightforward using the CRAY compilers on the AMD systems, the performance optimization required more fine-tuning. In the optimization effort, we uncovered code sections that had performed well on NVIDIA GPUs, but were unexpectedly slow on AMD GPUs. After AMD-targeted code optimizations, performance on AMD GPUs has increased to meet our expectations. Modest speed improvements were also seen on NVIDIA GPUs, which was an unexpected benefit of this exercise.
description: 6 pages, 4 figures, 2 tables, To be published in Proceedings of PEARC23
MPEC 2023-E73 : DAILY ORBIT UPDATE (2023 March 14)
Creators: name: Minor Planet Center Staff
Publisher: name: The Minor Planet Center
Year: 2023
Subjects: subject: Small Solar System bodies
valueUri: http://astrothesaurus.org/uat/1469

description: The Minor Planet Electronic Circulars contain information on unusual minor planets, routine data on comets and natural satellites, and occasional editorial announcements.  They are published on behalf of Division F of the International Astronomical Union by the Minor Planet Center, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
CONP Ethics Toolkit v1.0.1
Creators: name: Beauvais, Michael J.S.
name: Knoppers, Bartha Maria
name: Cavoukian, Ann
name: Clarkson, John
name: Green-Noble, Lindsay
name: Illes, Judy
name: Karamchandani, Jason
name: Nadler, Roland
name: Roskams-Edris, Dylan
name: Stewart, Walter
name: Bermudez, Patrick
name: Farrés, Marcel
name: Royer, Jessica
name: Zatorre, Robert
Publisher: name: Zenodo
Year: 2021
Subjects: ethics
privacy
law
open science
neuroscience
neuroethics
human subjects research regulation

description: CONP Ethics Toolkit consisting of: Model prospective consent clauses Retrospective consent filter De-identification information and tools This consent toolkit is the product of extended discussions and careful drafting that considers both Canadian and international ethical frameworks and research practice. In adapting this consent toolkit for your own research needs, we encourage you to mention to your research ethics board that your consent materials closely follow the templates created by the CONP Ethics and Governance Committee. The Committee's members include internationally recognized experts in research ethics, neuroethics, data governance, and law. The Committee's members are: Bartha Maria Knoppers (Chair), Michael Beauvais (Manager), Ann Cavoukian, John Clarkson, Lindsay Green-Noble, Judy Illes, Jason Karamchandani, Roland Nadler, Dylan Roskams-Edris, and Walter Stewart. Further feedback was graciously provided from members of the CONP community, in particular Patrick Bermudez, Marcel Farrés Franch, Jessica Royer, and Robert Zatorre. Full Changelog: https://github.com/CONP-PCNO/Ethics_and_Data_Governance/compare/v1.0...v1.0.1
On the local well-posedness of Lovelock and Horndeski theories
Creators: name: Papallo, Giuseppe
name: Reall, Harvey S.
Publisher: name: arXiv
Year: 2017
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We investigate local well-posedness of the initial value problem for Lovelock and Horndeski theories of gravity. A necessary condition for local well-posedness is strong hyperbolicity of the equations of motion. Even weak hyperbolicity can fail for strong fields so we restrict to weak fields. The Einstein equation is known to be strongly hyperbolic in harmonic gauge so we study Lovelock theories in harmonic gauge. We show that the equation of motion is always weakly hyperbolic for weak fields but, in a generic weak-field background, it is not strongly hyperbolic. For Horndeski theories, we prove that, for weak fields, the equation of motion is always weakly hyperbolic in any generalized harmonic gauge. For some Horndeski theories there exists a generalized harmonic gauge for which the equation of motion is strongly hyperbolic in a weak-field background. This includes "k-essence" like theories. However, for more general Horndeski theories, there is no generalized harmonic gauge for which the equation of motion is strongly hyperbolic in a generic weak-field background. Our results show that the standard method used to establish local well-posedness of the Einstein equation does not extend to Lovelock or general Horndeski theories. This raises the possibility that these theories may not admit a well-posed initial value problem even for weak fields.
description: v3: typos corrected and journal reference added. v2: results strengthened by requiring the generalised harmonic gauge condition for the linearised theory to arise as the linearisation of a generalised harmonic gauge condition for the nonlinear theory (discussion added at the end of Sec. 4.4). Added reference and corrected typos. Version accepted for publication in Phys.Rev.D. 46 pages
Direct measurement of the ballistic motion of a freely floating colloid in Newtonian and viscoelastic fluids
Creators: name: Hammond, Andrew P.
name: Corwin, Eric I.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Fluid Dynamics (physics.flu-dyn)
subject: FOS: Physical sciences

description: A thermal colloid suspended in a liquid will transition from a short time ballistic motion to a long time diffusive motion. However, the transition between ballistic and diffusive motion is highly dependent on the properties and structure of the particular liquid. We directly observe a free floating tracer particle's ballistic motion and its transition to the long time regime in both a Newtonian fluid and a viscoelastic Maxwell fluid. We examine the motion of the free particle in a Newtonian fluid and demonstrate a high degree of agreement with the accepted Clercx-Schram model for motion in a dense fluid. Measurements of the functional form of the ballistic-to-diffusive transition provide direct measurements of the temperature, viscosity, and tracer radius. We likewise measure the motion in a viscoelastic Maxwell fluid and find a significant disagreement between the theoretical asymptotic behavior and our measured values of the microscopic properties of the fluid. We observe a greatly increased effective mass for a freely moving particle and a decreased plateau modulus.
description: 5 pages, 4 figures
High scale flavor alignment in two-Higgs doublet models and its phenomenology
Creators: name: Gori, Stefania
name: Haber, Howard E.
name: Santos, Edward
Publisher: name: arXiv
Year: 2017
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: The most general two-Higgs doublet model (2HDM) includes potentially large sources of flavor changing neutral currents (FCNCs) that must be suppressed in order to achieve a phenomenologically viable model. The flavor alignment ansatz postulates that all Yukawa coupling matrices are diagonal when expressed in the basis of mass-eigenstate fermion fields, in which case tree-level Higgs mediated FCNCs are eliminated. In this work, we explore models with the flavor alignment condition imposed at a very high energy scale, which results in the generation of Higgs-mediated FCNCs via renormalization group running from the high energy scale to the electroweak scale. Using the current experimental bounds on flavor changing observables, constraints are derived on the aligned 2HDM parameter space. In the favored parameter region, we analyze the implications for Higgs boson phenomenology.
description: Explanations added. It matches the version published in JHEP
Maximal volume behind horizons without curvature singularity
Creators: name: Wang, Shao-Jun
name: Guo, Xin-Xuan
name: Wang, Towe
Publisher: name: arXiv
Year: 2017
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: The black hole information paradox is related to the area of event horizon, and potentially to the volume and singularity behind it. One example is the complexity/volume duality conjectured by Stanford and Susskind. Accepting the proposal of Christodoulou and Rovelli, we calculate the maximal volume inside regular black holes, which are free of curvature singularity, in asymptotically flat and anti-de Sitter spacetimes respectively. The complexity/volume duality is then applied to anti-de Sitter regular black holes. We also present an analytical expression for the maximal volume outside the de Sitter horizon.
description: 11 pages, 4 figures, Sect III improved
On the momentum broadening of in-medium jet evolution using a light-front Hamiltonian approach
Creators: name: Li, Meijian
name: Lappi, Tuomas
name: Zhao, Xingbo
name: Salgado, Carlos A.
Publisher: name: arXiv
Year: 2023
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: Following the non-perturbative light-front Hamiltonian formalism developed in our preceding work [Phys.Rev.D 104 (2021) 5, 056014], we investigate the momentum broadening of a quark jet inside a SU(3) colored medium. We perform the numerical simulation of the real-time jet evolution in Fock spaces of a single quark, a quark-gluon state, and coupled quark- and quark-gluon states at various jet momenta $p^+$ and medium densities. With the obtained jet light-front wavefunction, we extract the jet transverse momentum distribution, the quenching parameter, and the gluon emission rate. We analyze the dependence of momentum broadening on $p^+$, medium density, color configuration, spatial correlation, and medium-induced gluon emission. For comparison, we also derive analytically the expectation value of the transverse momentum of a quark-gluon state in any color configuration and in an arbitrary spatial distribution in the eikonal limit. This work can help understand jet momentum broadening in the non-eikonal regime.
Bayesian Numerical Integration with Neural Networks
Creators: name: Ott, Katharina
name: Tiemann, Michael
name: Hennig, Philipp
name: Briol, François-Xavier
Publisher: name: arXiv
Year: 2023
Subjects: subject: Machine Learning (stat.ML)
subject: Machine Learning (cs.LG)
subject: FOS: Computer and information sciences

description: Bayesian probabilistic numerical methods for numerical integration offer significant advantages over their non-Bayesian counterparts: they can encode prior information about the integrand, and can quantify uncertainty over estimates of an integral. However, the most popular algorithm in this class, Bayesian quadrature, is based on Gaussian process models and is therefore associated with a high computational cost. To improve scalability, we propose an alternative approach based on Bayesian neural networks which we call Bayesian Stein networks. The key ingredients are a neural network architecture based on Stein operators, and an approximation of the Bayesian posterior based on the Laplace approximation. We show that this leads to orders of magnitude speed-ups on the popular Genz functions benchmark, and on challenging problems arising in the Bayesian analysis of dynamical systems, and the prediction of energy production for a large-scale wind farm.
Parallel numerical modeling of hybrid-dimensional compositional non-isothermal Darcy flows in fractured porous media
Creators: name: Xing, Feng
name: Masson, Roland
name: Lopez, Simon
Publisher: name: arXiv
Year: 2016
Subjects: subject: Numerical Analysis (math.NA)
subject: FOS: Mathematics

description: This paper introduces a new discrete fracture model accounting for non-isothermal compositional multiphase Darcy flows and complex networks of fractures with intersecting, immersed and non immersed fractures. The so called hybrid-dimensional model using a 2D model in the fractures coupled with a 3D model in the matrix is first derived rigorously starting from the equi-dimensional matrix fracture model. Then, it is dis-cretized using a fully implicit time integration combined with the Vertex Approximate Gradient (VAG) finite volume scheme which is adapted to polyhedral meshes and anisotropic heterogeneous media. The fully coupled systems are assembled and solved in parallel using the Single Program Multiple Data (SPMD) paradigm with one layer of ghost cells. This strategy allows for a local assembly of the discrete systems. An efficient preconditioner is implemented to solve the linear systems at each time step and each Newton type iteration of the simulation. The numerical efficiency of our approach is assessed on different meshes, fracture networks, and physical settings in terms of parallel scalability, nonlinear convergence and linear convergence.
CONP Ethics Toolkit v1.0.4
Creators: name: Beauvais, Michael J.S.
name: Knoppers, Bartha Maria
name: Cavoukian, Ann
name: Clarkson, John
name: Green-Noble, Lindsay
name: Illes, Judy
name: Karamchandani, Jason
name: Nadler, Roland
name: Roskams-Edris, Dylan
name: Stewart, Walter
name: Bermudez, Patrick
name: Bernier, Alexander
name: Lemmens, Trudo
name: Farrés, Marcel
name: Royer, Jessica
name: Zatorre, Robert
Publisher: name: Zenodo
Year: 2023
Subjects: ethics
privacy
law
open science
neuroscience
neuroethics
human subjects research regulation

description: CONP Ethics Toolkit consisting of: Model prospective consent clauses Retrospective consent filter De-identification information and tools This consent toolkit is the product of extended discussions and careful drafting that considers both Canadian and international ethical frameworks and research practice. In adapting this consent toolkit for your own research needs, we encourage you to mention to your research ethics board that your consent materials are modeled after those created by the CONP Ethics and Governance Committee. The Committee's members include internationally recognized experts in research ethics, neuroethics, data governance, and law: Trudo Lemmens (Chair), Alexander Bernier (Manager), Ann Cavoukian, John Clarkson, Jason Karamchandani, Roland Nadler, Dylan Roskams-Edris, and Walter Stewart. Further feedback was graciously provided from members of the CONP community, in particular Patrick Bermudez, Marcel Farrés Franch, Jessica Royer, Robert Zatorre, and past Committee Members Bartha Maria Knoppers, Lindsay Green Noble, and Judy Illes. GitHub source: https://github.com/CONP-PCNO/Ethics_and_Data_Governance
Unions of admissible relations
Creators: name: Lipparini, Paolo
Publisher: name: arXiv
Year: 2017
Subjects: subject: Rings and Algebras (math.RA)
subject: FOS: Mathematics
subject: 08B10, 08B05

description: We show that a variety $\mathcal V$ is congruence distributive if and only if there is some $h$ such that the inclusion (1) $Θ\cap ( σ\circ σ) \subseteq ( Θ\cap σ) \circ ( Θ\cap σ) \circ \dots $ ($h$ factors) holds in every algebra in $\mathcal V$, for every tolerance $Θ$ and every U-admissible relation $σ$. By a U-admissible relation we mean a binary relation which is the set-theoretical union of a set of reflexive and admissible relations. For any fixed $h$, a Maltsev-type characterization is given for the inclusion (1). It is an open problem whether (1) is still equivalent to congruence distributivity when $Θ$ is assumed to be a $U$-admissible relation, rather than a tolerance. In both cases many equivalent formulations for (1) are presented. The results suggest that it might be interesting to study the structure of the set of U-admissible relations on an algebra, as well as identities dealing with such relations.
description: v.3, some improvements
Cataclysmic Variables from Sloan Digital Sky Survey V -- the search for period bouncers continues
Creators: name: Inight, K.
name: Gänsicke, Boris T.
name: Schwope, A.
name: Anderson, S. F.
name: Badenes, C.
name: Breedt, E.
name: Chandra, V.
name: Davies, B. D. R.
name: Fusillo, N. P. Gentile
name: Green, M. J.
name: Hermes, J. J.
name: Huamani, I. Achaica
name: Hwang, H.
name: Knauff, K.
name: Kurpas, J.
name: Long, K. S.
name: Malanushenko, V.
name: Morrison, S.
name: C., I. J. Quiroz
name: Ramos, G. N. Aichele
name: Roman-Lopes, A.
name: Schreiber, M. R.
name: Standke, A.
name: Stütz, L.
name: Thorstensen, J. R.
name: Toloza, O.
name: Tovmassian, G.
name: Zakamska, N. L.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: SDSS-V is carrying out a dedicated survey for white dwarfs, single and in binaries, and we report the analysis of the spectroscopy of cataclysmic variables (CVs) and CV candidates obtained during the final plug plate observations of SDSS. We identify eight new CVs, spectroscopically confirm 53 and refute eleven published CV candidates, and we report 21 new or improved orbital periods. Combined with previously published data, the orbital period distribution of the SDSS-V CVs does not clearly exhibit a period gap. This is consistent with previous findings that spectroscopically identified CVs have a larger proportion of short-period systems compared to samples identified from photometric variability. Remarkably, despite a systematic search, we find very few period bouncers. We estimate the space density of period bouncers to be $\simeq0.2\times10^{-6}\,\mathrm{pc}^{-3}$, i.e. they represent only a few per cent of the total CV population. This suggests that during their final phase of evolution, CVs either destroy the donor, e.g. via a merger, or that they become detached and cease mass transfer.
description: Accepted by MNRAS. Includes machine readable list of CVs
Elastocapillary Levelling of Thin Viscous Films on Soft Substrates
Creators: name: Rivetti, Marco
name: Bertin, Vincent
name: Salez, Thomas
name: Hui, Chung-Yuen
name: Linne, Christine
name: Arutkin, Maxence
name: Wu, Haibin
name: Raphaël, Elie
name: Bäumchen, Oliver
Publisher: name: arXiv
Year: 2017
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Materials Science (cond-mat.mtrl-sci)
subject: Chemical Physics (physics.chem-ph)
subject: Fluid Dynamics (physics.flu-dyn)
subject: FOS: Physical sciences

description: A thin liquid film with non-zero curvature at its free surface spontaneously flows to reach a flat configuration, a process driven by Laplace pressure gradients and resisted by the liquid's viscosity. Inspired by recent progresses on the dynamics of liquid droplets on soft substrates, we here study the relaxation of a viscous film supported by an elastic foundation. Experiments involve thin polymer films on elastomeric substrates, where the dynamics of the liquid-air interface is monitored using atomic force microscopy. A theoretical model that describes the coupled evolution of the solid-liquid and the liquid-air interfaces is also provided. In this soft-levelling configuration, Laplace pressure gradients not only drive the flow, but they also induce elastic deformations on the substrate that affect the flow and the shape of the liquid-air interface itself. This process represents an original example of elastocapillarity that is not mediated by the presence of a contact line. We discuss the impact of the elastic contribution on the levelling dynamics and show the departure from the classical self-similarities and power laws observed for capillary levelling on rigid substrates.
MPEC 2023-N12 : S/2019 S 6
Creators: name: Minor Planet Center Staff
Publisher: name: The Minor Planet Center
Year: 2023
Subjects: subject: Small Solar System bodies
valueUri: http://astrothesaurus.org/uat/1469

description: The Minor Planet Electronic Circulars contain information on unusual minor planets, routine data on comets and natural satellites, and occasional editorial announcements.  They are published on behalf of Division F of the International Astronomical Union by the Minor Planet Center, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
Resurgence Structure to All Orders of Multi-bions in Deformed SUSY Quantum Mechanics
Creators: name: Fujimori, Toshiaki
name: Kamata, Syo
name: Misumi, Tatsuhiro
name: Nitta, Muneto
name: Sakai, Norisuke
Publisher: name: arXiv
Year: 2017
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We investigate the resurgence structure in quantum mechanical models originating in 2d non-linear sigma models with emphasis on nearly supersymmetric and quasi-exactly solvable parameter regimes. By expanding the ground state energy in powers of a supersymmetry-breaking deformation parameter $δε$, we derive exact results for the expansion coefficients. In the class of models described by real multiplets, the ${\mathcal O}(δε)$ ground state energy has a non-Borel summable asymptotic series, which gives rise to imaginary ambiguities leading to rich resurgence structure. We discuss the sine-Gordon quantum mechanics (QM) as an example and show that the semiclassical contributions from complex multi-bion solutions correctly reproduce the corresponding part in the exact result including the imaginary ambiguities. As a typical model described by chiral multiplets, we discuss the $\mathbb C P^{N-1}$ QM and show that the exact ${\mathcal O}(δε)$ ground state energy can be completely reconstructed from the semiclassical multi-bion contributions. Although the ${\mathcal O}(δε)$ ground state energy has trivial resurgence structure, a simple but rich resurgence structure appears at ${\mathcal O}(δε^{2})$. We show the complete cancellation between the ${\mathcal O}(δε^{2})$ imaginary ambiguities arising from the non-Borel summable perturbation series and those in the semiclassical contributions of $N-1$ complex bion solutions. We also discuss the resurgence structure of a squashed ${\mathbb C}P^1$ QM.
description: 61 pages, 8 figures, references added, typos corrected
Large Language Models Can be Lazy Learners: Analyze Shortcuts in In-Context Learning
Creators: name: Tang, Ruixiang
name: Kong, Dehan
name: Huang, Longtao
name: Xue, Hui
Publisher: name: arXiv
Year: 2023
Subjects: subject: Computation and Language (cs.CL)
subject: Artificial Intelligence (cs.AI)
subject: Machine Learning (cs.LG)
subject: FOS: Computer and information sciences

description: Large language models (LLMs) have recently shown great potential for in-context learning, where LLMs learn a new task simply by conditioning on a few input-label pairs (prompts). Despite their potential, our understanding of the factors influencing end-task performance and the robustness of in-context learning remains limited. This paper aims to bridge this knowledge gap by investigating the reliance of LLMs on shortcuts or spurious correlations within prompts. Through comprehensive experiments on classification and extraction tasks, we reveal that LLMs are "lazy learners" that tend to exploit shortcuts in prompts for downstream tasks. Additionally, we uncover a surprising finding that larger models are more likely to utilize shortcuts in prompts during inference. Our findings provide a new perspective on evaluating robustness in in-context learning and pose new challenges for detecting and mitigating the use of shortcuts in prompts.
Heat capacity of a self-gravitating spherical shell of radiations
Creators: name: Kim, Hyeong-Chan
Publisher: name: arXiv
Year: 2017
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We study the heat capacity of a static system of self-gravitating radiations analytically in the context of general relativity. To avoid the complexity due to a conical singularity at the center, we excise the central part and replace it with a regular spherically symmetric distribution of matters of which specifications we are not interested in. We assume that the mass inside the inner boundary and the locations of the inner and the outer boundaries are given. Then, we derive a formula relating the variations of physical parameters at the outer boundary with those at the inner boundary. Because there is only one free variation at the inner boundary, the variations at the outer boundary are related, which determines the heat capacity. To get an analytic form for the heat capacity, we use the thermodynamic identity $δS_{\rm rad} = βδM_{\rm rad}$ additionally, which is derived from the variational relation of the entropy formula with the restriction that the mass inside the inner boundary does not change. Even if the radius of the inner boundary of the shell goes to zero, in the presence of a central conical singularity, the heat capacity does not go to the form of the regular sphere. An interesting discovery is that another legitimate temperature can be defined at the inner boundary which is different from the asymptotic one $β^{-1}$.
description: 13 pages, 2 figures, major corrections, to appear in Phys. Rev. D
Super-Walk Formulae for Even and Odd Laplacians in Finite Graphs
Creators: name: Yu, Chengzheng
Publisher: name: arXiv
Year: 2016
Subjects: subject: Combinatorics (math.CO)
subject: Mathematical Physics (math-ph)
subject: FOS: Mathematics
subject: FOS: Physical sciences

description: The number of walks from one vertex to another in a finite graph can be counted by the adjacency matrix. In this paper, we prove two theorems that connect the graph Laplacian with two types of walks in a graph. By defining two types of walks and giving orientation to a finite graph, one can easily count the number of the total signs of each kind of walk from one element to another of a fixed length.
description: 9 pages, 2 figures
Two-magnon excitations in resonant inelastic x-ray scattering studied by spin-density-wave formalism
Creators: name: Nomura, Takuji
Publisher: name: arXiv
Year: 2017
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We study two-magnon excitations in resonant inelastic x-ray scattering (RIXS) at the transition-metal $K$-edge. Instead of working with effective Heisenberg spin models, we work with a Hubbard-type model ($d$-$p$ model) for a typical insulating cuprate La$_2$CuO$_4$. For the antiferromagnetic ground state within the spin-density-wave (SDW) mean-field formalism, we calculate the dynamical correlation function within the random-phase approximation (RPA), and then obtain two-magnon excitation spectra by calculating the convolution of it. Coupling between the $K$-shell hole and the magnons in the intermediate state is calculated by means of diagrammatic perturbation expansion in the Coulomb interaction. Calculated momentum dependence of RIXS spectra agrees well with that of experiments. A notable difference from previous calculations based on the Heisenberg spin models is that RIXS spectra have a large two-magnon weight near the zone center, which may be confirmed by further careful high-resolution experiments.
description: 16 pages, 7 figures. Accepted to Phys. Rev. B
On classical $Z_2 \times Z_2$-graded Lie algebras
Creators: name: Stoilova, N. I.
name: Van der Jeugt, J.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Mathematical Physics (math-ph)
subject: Group Theory (math.GR)
subject: Rings and Algebras (math.RA)
subject: Representation Theory (math.RT)
subject: FOS: Physical sciences
subject: FOS: Mathematics

description: We construct classes of $Z_2 \times Z_2$-graded Lie algebras corresponding to the classical Lie algebras, in terms of their defining matrices. For the $Z_2 \times Z_2$-graded Lie algebra of type $A$, the construction coincides with the previously known class. For the $Z_2 \times Z_2$-graded Lie algebra of type $B$, $C$ and $D$ our construction is new and gives rise to interesting defining matrices closely related to the classical ones but undoubtedly different. We also give some examples and possible applications to parastatistics.
Reviewing BPMN as a Modeling Notation for CACAO Security Playbooks
Creators: name: Zych, Mateusz
name: Mavroeidis, Vasileios
name: Fysarakis, Konstantinos
name: Athanatos, Manos
Publisher: name: arXiv
Year: 2023
Subjects: subject: Cryptography and Security (cs.CR)
subject: FOS: Computer and information sciences

description: As cyber systems become increasingly complex and cybersecurity threats become more prominent, defenders must prepare, coordinate, automate, document, and share their response methodologies to the extent possible. The CACAO standard was developed to satisfy the above requirements, providing a common machine-readable framework and schema for documenting cybersecurity operations processes, including defensive tradecraft and tactics, techniques, and procedures. Although this approach is compelling, a remaining limitation is that CACAO provides no native modeling notation for graphically representing playbooks, which is crucial for simplifying their creation, modification, and understanding. In contrast, the industry is familiar with BPMN, a standards-based modeling notation for business processes that has also found its place in representing cybersecurity processes. This research examines BPMN and CACAO and explores the feasibility of using the BPMN modeling notation to represent CACAO security playbooks graphically. The results indicate that mapping CACAO and BPMN is attainable at an abstract level; however, conversion from one encoding to another introduces a degree of complexity due to the multiple ways CACAO constructs can be represented in BPMN and the extensions required in BPMN to support CACAO fully.
A Unique View of AGN-Driven Molecular Outflows: The Discovery of a Massive Galaxy Counterpart to a $z=2.4$ High-Metallicity Damped Lyman-$α$ Absorber
Creators: name: Rudie, Gwen C.
name: Newman, Andrew B.
name: Murphy, Michael T.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We report the discovery of a massive $\log(M/M_\odot)=10.74^{+0.18}_{-0.16}$ galaxy at the same redshift as a carbon-monoxide-bearing sub-damped Lyman $α$ absorber (sub-DLA) seen in the spectrum of QSO J1439+1117. The galaxy, J1439B, is located 4\farcs7 from the QSO sightline, a projected distance of 38 physical kpc at $z=2.4189$, and exhibits broad optical emission lines ($σ_{\rm{[O III]}}=303 \pm 12$~\kms) with ratios characteristic of excitation by an active galactic nucleus (AGN). The galaxy has a factor of $\sim$9 lower star formation than is typical of star-forming galaxies of the same mass and redshift. The nearby sub-DLA is highly enriched, suggesting its galactic counterpart must be massive if it follows the $z\sim2$ mass-metallicity relationship. Metallic absorption within the circumgalactic medium of the sub-DLA and J1439B is spread over a velocity range $Δv > 1000$ \kms, suggesting an energetic origin. We explore the possibility that a different galaxy could be responsible for the rare absorber, and conclude that it is unlikely based on imaging, integral-field spectroscopy, and high-$z$ massive galaxy pair statistics. We argue that the gas seen in absorption against the QSO was likely ejected from the galaxy J1439B and therefore provides a unique observational probe of AGN feedback in the distant universe.
description: 15 pages, 9 figures, accepted to ApJ
Gravity darkening in stars with surface differential rotation
Creators: name: Zorec, J.
name: Rieutord, M.
name: Lara, F. Espinosa
name: Frémat, Y.
name: de Souza, A. Domiciano
name: Royer, F.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: The interpretation of stellar apparent fundamental parameters must be treated consistently with the characteristics of their surface rotation law. We develop a model to determine the distribution of the effective temperature and gravity, which depend on the surface differential rotation law and on the stellar external geometry. The basic assumptions are: a) the atmosphric layers are in radiative equilibrium; b) the bolometric flux is anti-parallel with the effective gravity; c) the angular velocity in the surface is Omega=Omega(theta,alpha,k)] where (alpha,k) are free parameters. The effective temperature varies with co-latitude `theta' and on the differential-rotation law through the effective gravity and the gravity-darkening function (GDF). Although the derived expressions can be treated numerically, for some low integer values of k, analytical forms of the `integral ofcharacteristic curves', on which the determination of the GDF relies, are obtained. The effects of the quantities (eta,alpha,k) (eta=ratio between centrifugal and gravitational accelerations at the equator) on the determination of the Vsini parameter and on the `gravity-darkening exponent' are studied. Depending on the values of (eta,alpha,k) the velocity V in the derived Vsini may strongly deviate from the equatorial rotational velocity. It is shown that the von Zeipel's-like gravity-darkening exponent $β_1$ depends on all parameters $(η,α,k)$ and that its value also depends on the viewing-angle i. Hence, there no unique interpretation of this exponent determined empirically in terms of (i,alpha). The data on rotating stars should be analyzed by taking into account the rotational effects through the GDF, by assuming k=2 as a first approximation. Instead of the classical pair (eta,beta1), it would be more useful to determine the quantities (eta,alpha,i) to characterize stellar rotation.
Einstein and Jordan frame correspondence in quantum cosmology: Expansion-collapse duality
Creators: name: Mukherjee, Dipayan
name: Sahota, Harkirat Singh
Publisher: name: arXiv
Year: 2023
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: The conformal correspondence between FLRW universes in the Einstein and Jordan frames allows for an expansion-collapse duality -- an always expanding Einstein frame universe can have a dual Jordan frame description that is contracting forever. The scenario eventually runs into an apparent paradox. When a collapsing universe approaches singularity, the classical description of the spacetime becomes inadequate. The contracting Jordan frame universe is expected to develop quantum characteristics when its scale factor becomes sufficiently small. However, at the same time, the corresponding Einstein frame universe is expected to behave classically, due to the arbitrarily large size it has grown to. In this case, the conformal map appears to be providing a duality between a quantum effect-dominated universe and a universe behaving classically. We investigate the status of the conformal map at the quantum level in such a scenario, focusing on addressing this paradox. The Einstein and Jordan frame universes are quantized individually using the Wheeler-DeWitt prescription. We show that the classical conformal map holds true at the quantum level when compared through the expectation values of the scale factor operators in the two frames. The relative quantum fluctuation in the scale factor is found to be conformally invariant, and it increases in both the past and future directions according to the internal clock. Expectedly, the quantum fluctuations in the collapsing Jordan frame keep on increasing as it shrinks towards singularity. More surprisingly, the quantum fluctuations in the expanding Einstein frame keep on increasing as well, even as its classical scale factor becomes larger. Despite having drastically different cosmological evolutions, the rise in quantum characteristics in a collapsing frame implies the same in its expanding counterpart, thereby resolving the apparent paradox.
description: 15 pages, 4 figures, minor changes