cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
ASAT: Adaptively Scaled Adversarial Training in Time Series
Creators: name: Zhang, Zhiyuan
name: Li, Wei
name: Bao, Ruihan
name: Harimoto, Keiko
name: Wu, Yunfang
name: Sun, Xu
Publisher: name: arXiv
Year: 2021
Subjects: subject: Machine Learning (cs.LG)
subject: FOS: Computer and information sciences

description: Adversarial training is a method for enhancing neural networks to improve the robustness against adversarial examples. Besides the security concerns of potential adversarial examples, adversarial training can also improve the generalization ability of neural networks, train robust neural networks, and provide interpretability for neural networks. In this work, we introduce adversarial training in time series analysis to enhance the neural networks for better generalization ability by taking the finance field as an example. Rethinking existing research on adversarial training, we propose the adaptively scaled adversarial training (ASAT) in time series analysis, by rescaling data at different time slots with adaptive scales. Experimental results show that the proposed ASAT can improve both the generalization ability and the adversarial robustness of neural networks compared to the baselines. Compared to the traditional adversarial training algorithm, ASAT can achieve better generalization ability and similar adversarial robustness.
description: Accepted to Neurocomputing
A spectator-model way to transverse-momentum-dependent gluon distribution functions
Creators: name: Bacchetta, Alessandro
name: Celiberto, Francesco Giovanni
name: Radici, Marco
name: Taels, Pieter
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We present exploratory analyses of the 3D gluon content of the proton via a study of unpolarized and polarized gluon TMDs at twist-2, calculated in a spectator model for the parent nucleon. Our approach embodies a flexible parametrization for the spectator-mass function, suited to describe both moderate and small-$x$ effects. All these studies can serve as a useful guidance in the investigation of the gluon dynamics inside nucleons and nuclei, which constitutes one of the major goals of new-generation colliding machines, as the EIC, the HL-LHC, NICA, and the FPF.
description: 7 pages, 2 figures, contribution to the proceedings of the XXVIII International Workshop on Deep Inelastic Scattering and Related Subjects (DIS2021), Stony Brook, New York, USA, 12-16 April, 2021, version accepted for publication on SciPost Physics Proceedings
Analisis Cognitif Higher Order Thinking Skills (Hots) dan Lower Order Thinking Skills (Lots) Reading Comprehension Pada Buku Ajar Bahasa Inggris Kelas XII Kemendikbud 2018
Creators: name: Pratama, Yoga
name: Pitaloka, Roro Meifi
Publisher: name: Zenodo
Year: 2024

description: In general, there are special package book practice questionsReading Comprehension adjusted to students' level of thinking so that it can help students improve critical thinking as one of the basic cognitive abilities as explained by Bloom's. The purpose of this research is to evaluate the practice questions in sectionReading Comprehension in the textbookEFL class 12. To find out what the contents of the practice questions in sectionReading Comprehensionalready in line with the achievement of the 2013 curriculum which emphasizes the ability to think at a high level(I.E.). Descriptive-qualitative is applied as a research method. By using a listchecklist Based on the revised Bloom's taxonomy theory update, researchers found thatLOTS contributed a figure of 60.9%, whileI MEANis 39.1%. The results of this research are that the textbooks issued by the Ministry of Education and Culture are still inadequate and do not meet the needs of grade 12 students. The questions in the books are dominated byLOTS. Researchers suggest to curriculum designers, book writers and publishers that in the future they can provide more adequate and effective teaching materials so that they can improve students' cognitive abilities.
Quantum transport in the black-hole configuration of an atom condensate outcoupled through an optical lattice
Creators: name: de Nova, J. R. M.
name: Sols, F.
name: Zapata, I.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Quantum Gases (cond-mat.quant-gas)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: The outcoupling of a Bose-Einstein condensate through an optical lattice provides an interesting scenario to study quantum transport phenomena or the analog Hawking effect as the system can reach a quasi-stationary black-hole configuration. We devote this work to characterize the quantum transport properties of quasi-particles on top of this black-hole configuration by computing the corresponding scattering matrix. We find that most of the features can be understood in terms of the usual Schrödinger scattering. In particular, a transmission band appears in the spectrum, with the normal-normal transmission dominating over the anomalous-normal one. We show that this picture still holds in a realistic experimental situation where the actual Gaussian envelope of the optical lattice is considered. A peaked resonant structure is displayed near the upper end of the transmission band, which suggests that the proposed setup is a good candidate to provide a clear signal of spontaneous Hawking radiation.
description: 27 pages, 8 figures
Mixing by stirring: optimizing shapes and strategies
Creators: name: Eggl, Maximilian F.
name: Schmid, Peter J.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Fluid Dynamics (physics.flu-dyn)
subject: Optimization and Control (math.OC)
subject: FOS: Physical sciences
subject: FOS: Mathematics

description: The mixing of binary fluids by stirrers is a commonplace procedure in many industrial and natural settings, and mixing efficiency directly translates into more homogeneous final products, more enriched compounds, and often substantial economic savings in energy and input ingredients. Enhancements in mixing efficiency can be accomplished by unorthodox stirring protocols as well as modified stirrer shapes that utilize unsteady hydrodynamics and vortex-shedding features to instigate the formation of fluid filaments which ultimately succumb to diffusion and produce a homogeneous mixture. We propose a PDE-constrained optimization approach to address the problem of mixing enhancement for binary fluids. Within a gradient-based framework, we target the stirring strategy as well as the cross-sectional shape of the stirrers to achieve improved mixedness over a given time horizon and within a prescribed energy budget. The optimization produces a significant enhancement in homogeneity in the initially separated fluids, suggesting promising modifications to traditional stirring protocols.
description: 24 pages, 11 figures. accepted in Physical Review Fluids
Electrically tunable stacking domains and ferroelectricity in moiré superlattices
Creators: name: Bennett, Daniel
name: Remez, Benjamin
Publisher: name: arXiv
Year: 2021
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: It is well known that stacking domains form in moiré superlattices due to the competition between the interlayer van der Waals forces and intralayer elastic forces, which can be recognized as polar domains due to the local spontaneous polarization in bilayers without centrosymmetry. We propose a theoretical model which captures the effect of an applied electric field on the domain structure. The coupling between the spontaneous polarization and field leads to uneven relaxation of the domains, and a net polarization in the superlattice at nonzero fields, which is sensitive to the moiré period. We show that the dielectric response to the field reduces the stacking energy and leads to softer domains in all bilayers. We then discuss the recent observations of ferroelectricity in the context of our model.
Testing Lorentz invariance of dark matter with satellite galaxies
Creators: name: Bettoni, Dario
name: Nusser, Adi
name: Blas, Diego
name: Sibiryakov, Sergey
Publisher: name: arXiv
Year: 2017
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We develop the framework for testing Lorentz invariance in the dark matter sector using galactic dynamics. We consider a Lorentz violating (LV) vector field acting on the dark matter component of a satellite galaxy orbiting in a host halo. We introduce a numerical model for the dynamics of satellites in a galactic halo and for a galaxy in a rich cluster to explore observational consequences of such an LV field. The orbital motion of a satellite excites a time dependent LV force which greatly affects its internal dynamics. Our analysis points out key observational signatures which serve as probes of LV forces. These include modifications to the line of sight velocity dispersion, mass profiles and shapes of satellites. With future data and a more detailed modeling these signatures can be exploited to constrain a new region of the parameter space describing the LV in the dark matter sector.
description: 27 pages, 11 figures, 2 tables, 1 appendix. Minor corrections in section 4.3.3
Save the Planet, Feed the Star: How Super-Earths Survive Migration and Drive Disk Accretion
Creators: name: Fung, Jeffrey
name: Chiang, Eugene
Publisher: name: arXiv
Year: 2017
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: Two longstanding problems in planet formation include (1) understanding how planets survive migration, and (2) articulating the process by which protoplanetary disks disperse---and in particular how they accrete onto their central stars. We can go a long way toward solving both problems if the disk gas surrounding planets has no intrinsic diffusivity ("viscosity"). In inviscid, laminar disks, a planet readily repels gas away from its orbit. On short timescales, zero viscosity gas accumulates inside a planet's orbit to slow Type I migration by orders of magnitude. On longer timescales, multiple super-Earths (distributed between, say, $\sim$0.1--10 AU) can torque inviscid gas out of interplanetary space, either inward to feed their stars, or outward to be blown away in a wind. We explore this picture with 2D hydrodynamics simulations of Earths and super-Earths embedded in inviscid disks, confirming their slow/stalled migration even under gas-rich conditions, and showing that disk transport rates range up to $\sim$$10^{-7} M_\odot~{\rm yr^{-1}}$ and scale as $\dot{M} \propto ΣM_{\rm p}^{3/2}$, where $Σ$ is the disk surface density and $M_{\rm p}$ is the planet mass. Gas initially sandwiched between two planets is torqued past both into the inner and outer disks. In sum, sufficiently compact systems of super-Earths can clear their natal disk gas, in a dispersal history that may be complicated and non-steady, but which conceivably leads over Myr timescales to large gas depletions similar to those characterizing transition disks.
description: Accepted to ApJ
Attosecond multi-photon multi-electron dynamics
Creators: name: Kretschmar, M.
name: Hadjipittas, A.
name: Major, B.
name: Tümmler, J.
name: Will, I.
name: Nagy, T.
name: Vrakking, M. J. J.
name: Emmanouilidou, A.
name: Schütte, B.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Atomic Physics (physics.atom-ph)
subject: Optics (physics.optics)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Multi-electron dynamics in atoms and molecules very often occur on sub- to few-femtosecond timescales. The available intensities of extreme-ultraviolet (XUV) attosecond pulses have previously only allowed the time-resolved investigation of two-photon, two-electron interactions. Here we demonstrate attosecond control over double and triple ionization of argon atoms involving the absorption of up to five XUV photons. In an XUV-pump XUV-probe measurement using a pair of attosecond pulse trains (APTs), the Ar$^{2+}$ ion yield exhibits a weak delay dependence, showing that its generation predominantly results from the sequential emission of two electrons by photoabsorption from the two APTs. In contrast, the Ar$^{3+}$ ion yield exhibits strong modulations as a function of the delay, which is a clear signature of the simultaneous absorption of at least two XUV photons. The experimental results are well reproduced by numerical calculations that provide detailed insights into the ionization dynamics. Our results open up new opportunities for the investigation and control of multi-electron dynamics and complex electron correlation mechanisms on extremely short timescales.
description: 8 pages, 4 figures
Breached pair superfluidity: a brief review
Creators: name: Liu, W. Vincent
Publisher: name: arXiv
Year: 2021
Subjects: subject: Quantum Gases (cond-mat.quant-gas)
subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: Interior gap superfluidity was introduced together with Frank Wilczek. Later on together with our collaborators, we generalized this new possibility of superfluidity to a broader concept, breach pair superfluidity. In the occasion to celebrate Professor Frank Wilczek's seventieth birthday and his productive career in several major areas in physics, I dedicate this note to recall the exciting times of developing this idea, the main aspects of the proposed phase, and the discussion on its stability condition.
description: 10 pages, 1 figure, a chapter in Festschrift Volume in Honor of Frank Wilczek, World Scientific. Added references in revision
Spectroscopic twin to the hypervelocity sdO star US 708 and three fast sdB stars from the Hyper-MUCHFUSS project
Creators: name: Ziegerer, E.
name: Heber, U.
name: Geier, S.
name: Irrgang, A.
name: Kupfer, T.
name: Fürst, F.
name: Schaffenroth, J.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: Important tracers for the dark matter halo of the Galaxy are hypervelocity stars (HVSs), which are faster than the local escape velocity of the Galaxy and their slower counterparts, the high-velocity stars in the Galactic halo. Such HVSs are believed to be ejected from the Galactic Centre (GC) through tidal disruption of a binary by the super-massive black hole (Hills mechanism). The Hyper-MUCHFUSS survey aims at finding high-velocity potentially unbound hot subdwarf stars. We present the spectroscopic and kinematical analyses of a He-sdO as well as three candidates among the sdB stars using optical Keck/ESI and VLT (Xshooter, FORS) spectroscopy. Proper motions are determined by combining positions from early-epoch photographic plates with those derived from modern digital sky surveys. The Galactic rest frame velocities range from 203 km\,s$^{-1}$ to 660 km\,s$^{-1}$, indicating that most likely all four stars are gravitationally bound to the Galaxy. With $T_\text{eff}=47000$ K and a surface gravity of $\log g = 5.7$, SDSS J205030.39$-$061957.8 (J2050) is a spectroscopic twin of the hypervelocity He-sdO US 708. As for the latter, the GC is excluded as a place of origin based on the kinematic analysis. Hence, the Hills mechanism can be excluded for J2050. The ejection velocity is much more moderate ($385\pm79$ km\,s$^{-1}$) than that of US 708 ($998\pm68$ km\,s$^{-1}$). The binary thermonuclear supernova scenario suggested for US 708 would explain the observed properties of J2050 very well without pushing the model parameters to their extreme limits, as required for US 708. Accordingly, the star would be the surviving donor of a type Ia supernova. Three sdB stars also showed extreme kinematics; one could be a HVS ejected from the GC, whereas the other two could be ejected from the Galactic disk through the binary supernova mechanism. Alternatively, they might be extreme halo stars.
description: Accepted for publication by A&A
Optical nonreciprocity in rotating diamond with nitrogen-vacancy center
Creators: name: Huang, Hong-Bo
name: Lin, Jun-Jie
name: Yao, Yi-Xuan
name: Xia, Ke-Yu
name: Yin, Zhang-Qi
name: Ai, Qing
Publisher: name: arXiv
Year: 2021
Subjects: subject: Quantum Physics (quant-ph)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: We theoretically propose a method to realize optical nonreciprocity in rotating nano-diamond with a nitrogen-vacancy (NV) center. Because of the relative motion of the NV center with respect to the propagating fields, the frequencies of the fields are shifted due to the Doppler effect. When the control and probe fields are incident to the NV center from the same direction, the two-photon resonance still holds as the Doppler shifts of the two fields are the same. Thus, due to the electromagnetically-induced transparency (EIT), the probe light can pass through the NV center nearly without absorption. However, when the two fields propagate in opposite directions, the probe light can not effectively pass through the NV center as a result of the breakdown of two-photon resonance.
description: 7 pages, 4 figures
Inconsistency of Minkowski higher-derivative theories
Creators: name: Aglietti, Ugo G.
name: Anselmi, Damiano
Publisher: name: arXiv
Year: 2016
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We show that Minkowski higher-derivative quantum field theories are generically inconsistent, because they generate nonlocal, non-Hermitian ultraviolet divergences, which cannot be removed by means of standard renormalization procedures. By "Minkowski theories" we mean theories that are defined directly in Minkowski spacetime. The problems occur when the propagators have complex poles, so that the correlation functions cannot be obtained as the analytic continuations of their Euclidean versions. The usual power counting rules fail and are replaced by much weaker ones. Self-energies generate complex divergences proportional to inverse powers of D'Alembertians. Three-point functions give more involved nonlocal divergences, which couple to infrared effects. We illustrate the violations of the locality and Hermiticity of counterterms in scalar models and higher-derivative gravity.
description: 24 pages, 1 figure; v2: minor changes, EPJC
Do Babies Learn From the Impossible?
Creators: name: Lei, Yueyi
Publisher: name: University of Chicago
Year: 2022
Subjects: subject: core knowledge, naïve physics, naïve psychology, social learning, infancy, cognitive development

description: Based on core knowledge theory and several empirical findings, infants have basic expectations on objects and humans. These expectations are influential in infants’ learning. Previous studies have found that infants’ learning is promoted when objects previously violated physical principles, while learning is attenuated when people previously violated psychological principles. For instance, when infants see an object passes through a solid wall that violates principles of naïve physics, they want to explore and learn more about the object. Nevertheless, when infants see a person who grabs a ball inefficiently, which violates the principles of naïve psychology, infants do not choose to subsequently learn from that person. These findings raise the question of why expectancy violations in the object and social domains influence learning differently. In this thesis, we tested if seeing someone performing impossible actions by violating the physical principles would enhance or hinder 17 to 19-month-old infants' social learning from the person. We found no evidence that seeing human behaviors violate the naïve physics influence 17 to 19-month-old infants’ social learning.
Identifying Influential Nodes in Two-mode Data Networks using Formal Concept Analysis
Creators: name: Ibrahim, Mohamed-Hamza
name: Missaoui, Rokia
name: Vaillancourt, Jean
Publisher: name: arXiv
Year: 2021
Subjects: subject: Social and Information Networks (cs.SI)
subject: Artificial Intelligence (cs.AI)
subject: FOS: Computer and information sciences

description: Identifying important actors (or nodes) in a two-mode network often remains a crucial challenge in mining, analyzing, and interpreting real-world networks. While traditional bipartite centrality indices are often used to recognize key nodes that influence the network information flow, they frequently produce poor results in intricate situations such as massive networks with complex local structures or a lack of complete knowledge about the network topology and certain properties. In this paper, we introduce Bi-face (BF), a new bipartite centrality measurement for identifying important nodes in two-mode networks. Using the powerful mathematical formalism of Formal Concept Analysis, the BF measure exploits the faces of concept intents to identify nodes that have influential bicliques connectivity and are not located in irrelevant bridges. Unlike off-the shelf centrality indices, it quantifies how a node has a cohesive-substructure influence on its neighbour nodes via bicliques while not being in network core-peripheral ones through its absence from non-influential bridges. Our experiments on several real-world and synthetic networks show the efficiency of BF over existing prominent bipartite centrality measures such as betweenness, closeness, eigenvector, and vote-rank among others.
An area-depth symmetric $q,t$-Catalan polynomial
Creators: name: Pappe, Joseph
name: Paul, Digjoy
name: Schilling, Anne
Publisher: name: arXiv
Year: 2021
Subjects: subject: Combinatorics (math.CO)
subject: FOS: Mathematics
subject: Primary 05A19, 05E10, Secondary 05C05, 05C30

description: We define two symmetric $q,t$-Catalan polynomials in terms of the area and depth statistic and in terms of the dinv and dinv of depth statistics. We prove symmetry using an involution on plane trees. The same involution proves symmetry of the Tutte polynomials. We also provide a combinatorial proof of a remark by Garsia et al. regarding parking functions and the number of connected graphs on a fixed number of vertices.
description: 17 pages; v2 references added; v3 typos fixed, version to appear in Electronic J. Combinatorics
Effects of dark energy on the efficiency of charged AdS black holes as heat engine
Creators: name: Liu, Hang
name: Meng, Xin-He
Publisher: name: arXiv
Year: 2017
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: In this paper, we study the heat engine where charged AdS black holes surrounded by dark energy is the working substance and the mechanical work is done via $PdV$ term in the first law of black hole thermodynamics in the extended phase space. We first investigate the effects of a kind of dark energy (quintessence field in this paper) on the efficiency of the RN-AdS black holes as heat engine defined as a rectangle closed path in the $P-V$ plane. We get the exact efficiency formula and find that quintessence field can improve the heat engine efficiency which will increase as the field density $ρ_q$ grows. At some fixed parameters, we find that bigger volume difference between the smaller black holes($V_1$) and the bigger black holes($V_2$ ) will lead to a lower efficiency, while the bigger pressure difference $P_1-P_4$ will make the efficiency higher but it is always smaller than 1 and will never be beyond Carnot efficiency which is the maximum value of the efficiency constrained by thermodynamics laws, this is consistent to the heat engine in traditional thermodynamics. After making some special choices for thermodynamical quantities, we find that the increase of electric charge $Q$ and normalization factor $a$ can also promote heat engine efficiency which would infinitely approach the Carnot limit when $Q$ or $a$ goes to infinity.
description: 28 pages, 16 figures, refernces added, discussion and computation improved
Birkhoff-James Orthogonality in the Trace Norm, with Applications to Quantum Resource Theories
Creators: name: Johnston, Nathaniel
name: Moein, Shirin
name: Pereira, Rajesh
name: Plosker, Sarah
Publisher: name: arXiv
Year: 2021
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences
subject: 15A03, 15A60, 15B57, 81P40

description: We develop numerous results that characterize when a complex Hermitian matrix is Birkhoff-James orthogonal, in the trace norm, to a (Hermitian) positive semidefinite matrix or set of positive semidefinite matrices. For example, we develop a simple-to-test criterion that determines which Hermitian matrices are Birkhoff-James orthogonal, in the trace norm, to the set of all positive semidefinite diagonal matrices. We then explore applications of our work in the theory of quantum resources. For example, we characterize exactly which quantum states have modified trace distance of coherence equal to 1 (the maximal possible value), and we establish a connection between the modified trace distance of 2-entanglement and the NPPT bound entanglement problem.
description: 18 pages
Simultaneous Object Reconstruction and Grasp Prediction using a Camera-centric Object Shell Representation
Creators: name: Chavan-Dafle, Nikhil
name: Popovych, Sergiy
name: Agrawal, Shubham
name: Lee, Daniel D.
name: Isler, Volkan
Publisher: name: arXiv
Year: 2021
Subjects: subject: Robotics (cs.RO)
subject: FOS: Computer and information sciences

description: Being able to grasp objects is a fundamental component of most robotic manipulation systems. In this paper, we present a new approach to simultaneously reconstruct a mesh and a dense grasp quality map of an object from a depth image. At the core of our approach is a novel camera-centric object representation called the "object shell" which is composed of an observed "entry image" and a predicted "exit image". We present an image-to-image residual ConvNet architecture in which the object shell and a grasp-quality map are predicted as separate output channels. The main advantage of the shell representation and the corresponding neural network architecture, ShellGrasp-Net, is that the input-output pixel correspondences in the shell representation are explicitly represented in the architecture. We show that this coupling yields superior generalization capabilities for object reconstruction and accurate grasp quality estimation implicitly considering the object geometry. Our approach yields an efficient dense grasp quality map and an object geometry estimate in a single forward pass. Both of these outputs can be used in a wide range of robotic manipulation applications. With rigorous experimental validation, both in simulation and on a real setup, we show that our shell-based method can be used to generate precise grasps and the associated grasp quality with over 90% accuracy. Diverse grasps computed on shell reconstructions allow the robot to select and execute grasps in cluttered scenes with more than 93% success rate.
description: 18 pages, 12 figures, 8 tables
Asymptotic growth of Mordell-Weil ranks of elliptic curves in noncommutative towers
Creators: name: Ray, Anwesh
Publisher: name: arXiv
Year: 2021
Subjects: subject: Number Theory (math.NT)
subject: FOS: Mathematics
subject: 11G05, 11R23

description: Let $E$ be an elliptic curve defined over a number field $F$ with good ordinary reduction at all primes above $p$, and let $F_\infty$ be a finitely ramified uniform pro-$p$ extension of $F$ containing the cyclotomic $\mathbb{Z}_p$-extension $F_{cyc}$. Set $F^{(n)}$ be the $n$-th layer of the tower, and $F^{(n)}_{cyc}$ the cyclotomic $\mathbb{Z}_p$-extension of $F^{(n)}$. We study the growth of the rank of $E(F^{(n)})$ by analyzing the growth of the $λ$-invariant of the Selmer group over $F^{(n)}_{cyc}$ as $n\rightarrow \infty$. This method has its origins in work of A.Cuoco, who studied $\mathbb{Z}_p^2$-extensions. Refined estimates for growth are proved that are close to conjectured estimates. The results are illustrated in special cases.
description: 12 pages, final version, to appear in Canadian Math. Bull
Connecting Low-Loss Subspace for Personalized Federated Learning
Creators: name: Hahn, Seok-Ju
name: Jeong, Minwoo
name: Lee, Junghye
Publisher: name: arXiv
Year: 2021
Subjects: subject: Machine Learning (cs.LG)
subject: Artificial Intelligence (cs.AI)
subject: FOS: Computer and information sciences

description: Due to the curse of statistical heterogeneity across clients, adopting a personalized federated learning method has become an essential choice for the successful deployment of federated learning-based services. Among diverse branches of personalization techniques, a model mixture-based personalization method is preferred as each client has their own personalized model as a result of federated learning. It usually requires a local model and a federated model, but this approach is either limited to partial parameter exchange or requires additional local updates, each of which is helpless to novel clients and burdensome to the client's computational capacity. As the existence of a connected subspace containing diverse low-loss solutions between two or more independent deep networks has been discovered, we combined this interesting property with the model mixture-based personalized federated learning method for improved performance of personalization. We proposed SuPerFed, a personalized federated learning method that induces an explicit connection between the optima of the local and the federated model in weight space for boosting each other. Through extensive experiments on several benchmark datasets, we demonstrated that our method achieves consistent gains in both personalization performance and robustness to problematic scenarios possible in realistic services.
description: Appears at ACM SIGKDD 2022. Code available at http://github.com/vaseline555/SuPerFed
Quantum hardware calculations of periodic systems with partition-measurement symmetry verification: simplified models of hydrogen chain and iron crystals
Creators: name: Yamamoto, Kentaro
name: Manrique, David Zsolt
name: Khan, Irfan
name: Sawada, Hideaki
name: Ramo, David Muñoz
Publisher: name: arXiv
Year: 2021
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Running quantum algorithms on real hardware is essential for understanding their strengths and limitations, especially in the noisy intermediate scale quantum (NISQ) era. Herein we focus on the practical aspect of quantum computational calculations of solid-state crystalline materials based on theory developed in our group by using real quantum hardware with a novel noise mitigation technique referred to as partition-measurement symmetry verification, which performs post-selection of shot counts based on $Z_{2}$ and $U_{1}$ symmetry verification. We select two periodic systems with different level of complexity for these calculations. One of them is the distorted hydrogen chain as an example of very simple systems, and the other one is iron crystal in the BCC and FCC phases as it is considered to be inaccessible by using classical computational wavefunction methods. The ground state energies are evaluated based on the translational quantum subspace expansion (TransQSE) method for the hydrogen chain, and periodic boundary condition adapted VQE for our iron models. By applying these techniques for the simplest 2 qubit iron model systems, the correlation energies obtained by the hardware calculations agree with those of the state-vector simulations within $\sim$5 kJ/mol. Although the quantum computational resources used for those experiments are still limited, the techniques applied to obtain our simplified models will be applicable in essentially the same manner to more complicated cases as quantum hardware matures.
Dark matter in the Sun: scattering off electrons vs nucleons
Creators: name: Garani, Raghuveer
name: Palomares-Ruiz, Sergio
Publisher: name: arXiv
Year: 2017
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: The annihilation of dark matter (DM) particles accumulated in the Sun could produce a flux of neutrinos, which is potentially detectable with neutrino detectors/telescopes and the DM elastic scattering cross section can be constrained. Although the process of DM capture in astrophysical objects like the Sun is commonly assumed to be due to interactions only with nucleons, there are scenarios in which tree-level DM couplings to quarks are absent, and even if loop-induced interactions with nucleons are allowed, scatterings off electrons could be the dominant capture mechanism. We consider this possibility and study in detail all the ingredients necessary to compute the neutrino production rates from DM annihilations in the Sun (capture, annihilation and evaporation rates) for velocity-independent and isotropic, velocity-dependent and isotropic and momentum-dependent scattering cross sections for DM interactions with electrons and compare them with the results obtained for the case of interactions with nucleons. Moreover, we improve the usual calculations in a number of ways and provide analytical expressions in three appendices. Interestingly, we find that the evaporation mass in the case of interactions with electrons could be below the GeV range, depending on the high-velocity tail of the DM distribution in the Sun, which would open a new mass window for searching for this type of scenarios.
description: 37 pages, 5 figures. In memory of Haim Goldberg; v2: minor changes, updated references. Matches published version
Inner functions of matrix argument and conjugacy classes in unitary groups
Creators: name: Neretin, Yury A.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Complex Variables (math.CV)
subject: Group Theory (math.GR)
subject: FOS: Mathematics
subject: 32A30, 30J05, 32M15, 22E46, 47A06

description: Denote by $B_n$ the set of complex square matrices of order $n$, whose Euclidean operator norms are $<1$. Its Shilov boundary is the set $U(n)$ of all unitary matrices. A holomorphic map $B_m\to B_n$ is inner if it sends $U(m)$ to $U(n)$. On the other hand we consider a group $U(n+mj)$ and its subgroup $U(j)$ embedded to $U(n+mj)$ in a block-diagonal way ($m$ blocks $U(j)$ and a unit block of size $n$). For any conjugacy class of $U(n+mj)$ with respect to $U(j)$ we assign a 'characteristic function', which is a rational inner map $B_m\to B_n$. We show that the class of inner functions, which can be obtained as 'characteristic functions', is closed with respect to natural operations as pointwise direct sums, pointwise products, compositions, substitutions to finite-dimensional representations of general linear groups, etc. We also describe explicitly the corresponding operations on conjugacy classes.
description: 18p
Non-perturbative field theoretical aspects of graphene and related systems
Creators: name: Olivares, Juan Angel Casimiro
name: Mizher, Ana Julia
name: Raya, Alfredo
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Other Condensed Matter (cond-mat.other)
subject: FOS: Physical sciences

description: In this article, we review the dynamics of charge carriers in graphene and related 2D systems from a quantum field theoretical point of view. By allowing the electromagnetic fields to propagate throughout space and constraining fermions to move on a 2D manifold, the effective theory of such systems becomes a non-local version of quantum electrodynamics (QED) dubbed in literature pseudo or reduced QED. We review some aspects of the theory assuming the coupling arbitrary in strength. In particular, we focus on the chiral symmetry breaking scenarios and the analytical structure of the fermion propagator in vacuum and under the influence of external agents like a heat bath, in the presence of a Chern-Simons term, anisotropy and in curved space. We briefly discuss the major advances and some new results on this field.
description: Published version: 2 figs added, refs added, eq. typos corrected
A Meta-Learning Approach for Training Explainable Graph Neural Networks
Creators: name: Spinelli, Indro
name: Scardapane, Simone
name: Uncini, Aurelio
Publisher: name: arXiv
Year: 2021
Subjects: subject: Machine Learning (cs.LG)
subject: Machine Learning (stat.ML)
subject: FOS: Computer and information sciences

description: In this paper, we investigate the degree of explainability of graph neural networks (GNNs). Existing explainers work by finding global/local subgraphs to explain a prediction, but they are applied after a GNN has already been trained. Here, we propose a meta-learning framework for improving the level of explainability of a GNN directly at training time, by steering the optimization procedure towards what we call `interpretable minima'. Our framework (called MATE, MetA-Train to Explain) jointly trains a model to solve the original task, e.g., node classification, and to provide easily processable outputs for downstream algorithms that explain the model's decisions in a human-friendly way. In particular, we meta-train the model's parameters to quickly minimize the error of an instance-level GNNExplainer trained on-the-fly on randomly sampled nodes. The final internal representation relies upon a set of features that can be `better' understood by an explanation algorithm, e.g., another instance of GNNExplainer. Our model-agnostic approach can improve the explanations produced for different GNN architectures and use any instance-based explainer to drive this process. Experiments on synthetic and real-world datasets for node and graph classification show that we can produce models that are consistently easier to explain by different algorithms. Furthermore, this increase in explainability comes at no cost for the accuracy of the model.
Neutrino mixing and $R_K$ anomaly in $U(1)_X$ models: a bottom-up approach
Creators: name: Bhatia, Disha
name: Chakraborty, Sabyasachi
name: Dighe, Amol
Publisher: name: arXiv
Year: 2017
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We identify a class of $U(1)_X$ models which can explain the $R_K$ anomaly and the neutrino mixing pattern, by using a bottom-up approach. The different $X$-charges of lepton generations account for the lepton universality violation required to explain $R_K$. In addition to the three right-handed neutrinos needed for the Type-I seesaw mechanism, these minimal models only introduce an additional doublet Higgs and a singlet scalar. While the former helps in reproducing the quark mixing structure, the latter gives masses to neutrinos and the new gauge boson $Z^\prime$. Our bottom-up approach determines the $X$-charges of all particles using theoretical consistency and experimental constraints. We find the parameter space allowed by the constraints from neutral meson mixing, rare $b\to s$ decays and direct collider searches for $Z^\prime$. Such a $Z^\prime$ may be observable at the ongoing run of the Large Hadron Collider with a few hundred fb$^{-1}$ of integrated luminosity.
description: 29 pages, 6 figures, minor typos corrected, one comment and references added, matches with the version published in JHEP
Local and global scalar curvature rigidity of Einstein manifolds
Creators: name: Dahl, Mattias
name: Kroencke, Klaus
Publisher: name: arXiv
Year: 2021
Subjects: subject: Differential Geometry (math.DG)
subject: FOS: Mathematics
subject: Primary 53C25, Secondary 53C24, 58J05

description: An Einstein manifold is called scalar curvature rigid if there are no compactly supported volume-preserving deformation of the metric which increase the scalar curvature. We give various characterizations of scalar curvature rigidity for open Einstein manifolds as well as for closed Einstein manifolds. As an application, we construct mass-decreasing perturbations of the Riemannian Schwarzschild metric and the Taub-Bolt metric.
description: 44 pages, final version, to appear in Math. Ann
Polügeenne riskiskoor ennustab südame isheemiatõve riski oluliselt varem kui traditsioonilised riskitegurid
Creators: name: Viigimaa, Margus
Publisher: name: Eesti Arst
Year: 2020

description: Eesti Arst 2020; 99(5):322–324
description: Eesti Arst, 2020: Mai
Geometric theory of meromorphic functions
Creators: name: Eremenko, Alexandre
Publisher: name: arXiv
Year: 2021
Subjects: subject: Complex Variables (math.CV)
subject: FOS: Mathematics
subject: 30D30, 30D35, 30F45

description: This is a survey of results on the following problem. Consider a simply connected Riemann surface spread over the Riemann sphere. How are the properties of the uniformizing function of this surface related to the geometric properties of the surface? Based on the lecture in U. Michigan in May 2006.
description: 18 pages
Geneetiliselt määratud kardiovaskulaarse riski skoori kliiniline tähendus veel kaheldav
Creators: name: Reile Juhanson, Refereerinud
Publisher: name: Eesti Arst
Year: 2020

description: Eesti Arst 2020; 99(5):322–324
description: Eesti Arst, 2020: Mai
MARTINI: Smart Meter Driven Estimation of HVAC Schedules and Energy Savings Based on WiFi Sensing and Clustering
Creators: name: Nweye, Kingsley
name: Nagy, Zoltan
Publisher: name: arXiv
Year: 2021
Subjects: subject: Systems and Control (eess.SY)
subject: Machine Learning (cs.LG)
subject: FOS: Electrical engineering, electronic engineering, information engineering
subject: FOS: Computer and information sciences

description: HVAC systems account for a significant portion of building energy use. Nighttime setback scheduling is an energy conservation measure where cooling and heating setpoints are increased and decreased respectively during unoccupied periods with the goal of obtaining energy savings. However, knowledge of a building's real occupancy is required to maximize the success of this measure. In addition, there is the need for a scalable way to estimate energy savings potential from energy conservation measures that is not limited by building specific parameters and experimental or simulation modeling investments. Here, we propose MARTINI, a sMARt meTer drIveN estImation of occupant-derived HVAC schedules and energy savings that leverages the ubiquity of energy smart meters and WiFi infrastructure in commercial buildings. We estimate the schedules by clustering WiFi-derived occupancy profiles and, energy savings by shifting ramp-up and setback times observed in typical/measured load profiles obtained by clustering smart meter energy profiles. Our case-study results with five buildings over seven months show an average of 8.1%-10.8% (summer) and 0.2%-5.9% (fall) chilled water energy savings when HVAC system operation is aligned with occupancy. We validate our method with results from building energy performance simulation (BEPS) and find that estimated average savings of MARTINI are within 0.9%-2.4% of the BEPS predictions. In the absence of occupancy information, we can still estimate potential savings from increasing ramp-up time and decreasing setback start time. In 51 academic buildings, we find savings potentials between 1%-5%.
description: submitted
Patohistoloogilise diagnostika digilahendused Eestis
Creators: name: Semjonov, Eero
name: Minajeva, Ave
name: Džaparidze, Georgi
name: Gvozdkov, Alexander
name: Tamp, Erik
Publisher: name: Eesti Arst
Year: 2020

description: Eesti Arst 2020; 99(5):320–321
description: Eesti Arst, 2020: Mai
Measurement of Intermittency for Charged Particles in Au + Au Collisions at $\sqrt{s_\mathrm{NN}}$ = 7.7-200 GeV from STAR
Creators: name: Wu, Jin
Publisher: name: arXiv
Year: 2021
Subjects: subject: Nuclear Experiment (nucl-ex)
subject: FOS: Physical sciences

description: Local density fluctuations near the QCD critical point can be probed by intermittency analysis of scaled factorial moments in relativistic heavy-ion collisions. We report the first measurement of intermittency for charged particles in Au + Au collisions at $\sqrt{s_\mathrm{NN}}$ = 7.7-200 GeV from the STAR experiment at RHIC. We observe scaling behaviors in central Au + Au collisions, with the extracted scaling exponent decreasing from mid-central to the most central Au + Au collisions. Furthermore, the scaling exponent exhibits a non-monotonic energy dependence with a minimum around $\sqrt{s_\mathrm{NN}}$ = 20-30 GeV in central Au + Au collisions.
description: 5 pages, 4 figures; Revised version for the 50th International Symposium on Multiparticle Dynamics (ISMD 2021)
Surfing on turbulence: a strategy for planktonic navigation
Creators: name: Monthiller, Rémi
name: Loisy, Aurore
name: Koehl, Mimi A. R.
name: Favier, Benjamin
name: Eloy, Christophe
Publisher: name: arXiv
Year: 2021
Subjects: subject: Fluid Dynamics (physics.flu-dyn)
subject: Biological Physics (physics.bio-ph)
subject: FOS: Physical sciences

description: In marine plankton, many swimming species can perceive their environment with flow sensors. Can they use this flow information to travel faster in turbulence? To address this question, we consider plankters swimming at constant speed, whose goal is to move upwards. We propose a robust analytical behavior that allows plankters to choose a swimming direction according to the local flow gradients. We show numerically that such plankters can "surf" on turbulence and reach net vertical speeds up to twice their swimming speed. This new physics-based model suggests that planktonic organisms can exploit turbulence features for navigation.
description: Article: 5 pages, 5 figures. Supplemental: 11 pages, 6 figures. For associated open-source code, see https://github.com/C0PEP0D/sheld0n
Vastupidavustreening – kas rohkem on parem?
Creators: name: Rätsep, Rene
name: Teeäär, Tuuli
Publisher: name: Eesti Arst
Year: 2020

description: Arvestades vastupidavustreeningu kasvavat populaarsust ning treeningukoormuste suurenemist harrastajate seas, muutub üha aktuaalsemaks küsimus treeningu mõjust tervisele. Viimase kümne aasta teadusuuringutes on viidatud suuremahulise vastupidavustreeningu (näiteks pikamaajooksu, ­suusatamise ja ­jalgrattaspordi) võimalikule ebasoodsale mõjule südame­veresoonkonnale, mistõttu on selle kasulikkus tervisele küsimärgi alla sattunud. Artiklis on antud ülevaade suuremahulise vastupidavustreeningu mõjust südame­veresoonkonna tervisele eeskätt tervetel täiskasvanud harrastussportlastel.
description: Eesti Arst, 2020: Mai
Applications of ball spaces theory: fixed point theorems in semimetric spaces and ball convergence
Creators: name: Nowakowski, Piotr
name: Turoboś, Filip
Publisher: name: arXiv
Year: 2021
Subjects: subject: General Topology (math.GN)
subject: FOS: Mathematics
subject: 54E25, 47H10, 54A05

description: In the paper we apply some of the results from the theory of ball spaces in the semimetric spaces. This allowed us to obtain some fixed point theorems which we believe to be unknown to this day. We also show the limitations of the ball space approach to this topic. As a byproduct, we obtain the equivalence of some different notions of completness in semimetric spaces where the distance function is $1$-continuous. In the second part of the article, we generalize Caristi-Kirk results for for $b$-metric spaces. Additionally, we obtain characterization of semicompleteness for $1$-continuous $b$-metric space via fixed point theorem analogous to the result of Suzuki. In the epilogue, we introduce the concept of convergence in ball spaces, based on the idea that balls should resemble closed sets in topological sets. We prove several of its properties, compare it with convergence in semimetric spaces and pose several open questions connected with this notion.