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Wilson line-based action for gluodynamics at the loop level

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arXiv 2024年

作者： Kakkad, Hiren Kotko, Piotr Stasto, Anna AGH University Faculty of Physics and Applied Computer Science al. Mickiewicza 30 Krakow30-059 Poland The Pennsylvania State University Physics Department 104 Davey Lab University ParkPA16802 United States

We develop quantum corrections to the Wilson line-based action which we recently derived through a transformation that eliminates triple gluon vertices from the Yang-Mills action on the light-cone. The action efficiently computes high multiplicity tree-level split-helicity amplitudes with the number of diagrams following the Delannoy number series. However, the absence of the triple gluon vertices results in missing loop contributions. To remedy this, we develop two equivalent approaches using the one-loop effective action method to systematically incorporate loop contributions to our action. In one approach there are solely Yang-Mills vertices in the loop whereas the other uses the interaction vertices of our action along with the kernels of the solution of our transformation in the loop. In addition to demonstrating the equivalence of both approaches, we validated the quantum completeness of the former by computing all 4-point one-loop amplitudes which could not be previously computed. Both of our approaches are easily extendable to develop quantum corrections to other reformulations of the Yang-Mills theory obtained via non-linear classical field transformations eliminating interaction vertices. Copyright © 2024, The Authors. All rights reserved.

关键词： Linear transformations

Coevolutionary Algorithm for Building Robust Decision Trees under Minimax Regret

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arXiv 2023年

作者： Zychowski, Adam Perrault, Andrew Mańdziuk, Jacek Faculty of Mathematics and Information Science Warsaw University of Technology Poland Department of Computer Science and Engineering The Ohio State University United States Faculty of Computer Science AGH University of Krakow Poland Center of Excellence in Artificial Intelligence AGH University of Krakow Poland

In recent years, there has been growing interest in developing robust machine learning (ML) models that can withstand adversarial attacks, including one of the most widely adopted, efficient, and interpretable ML algorithms—decision trees (DTs). This paper proposes a novel coevolutionary algorithm (CoEvoRDT) designed to create robust DTs capable of handling noisy high-dimensional data in adversarial contexts. Motivated by the limitations of traditional DT algorithms, we leverage adaptive coevolution to allow DTs to evolve and learn from interactions with perturbed input data. CoEvoRDT alternately evolves competing populations of DTs and perturbed features, enabling construction of DTs with desired properties. CoEvoRDT is easily adaptable to various target metrics, allowing the use of tailored robustness criteria such as minimax regret. Furthermore, CoEvoRDT has potential to improve the results of other state-of-the-art methods by incorporating their outcomes (DTs they produce) into the initial population and optimize them in the process of coevolution. Inspired by the game theory, CoEvoRDT utilizes mixed Nash equilibrium to enhance convergence. The method is tested on 20 popular datasets and shows superior performance compared to 4 state-of-the-art algorithms. It outperformed all competing methods on 13 datasets with adversarial accuracy metrics, and on all 20 considered datasets with minimax regret. Strong experimental results and flexibility in choosing the error measure make CoEvoRDT a promising approach for constructing robust DTs in real-world applications. © 2023, CC BY.

关键词： Decision trees

Harnessing Parasitic Cavity as Reference for Low Coherence Systems

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Harnessing Parasitic Cavity as Reference for Low Coherence S...

2024 IEEE Photonics Conference, IPC 2024

作者： Robalinho, Paulo Rodrigues, A. Novais, S. Lobo Ribeiro, A.B. Silva, S. Frazão, O. Institute for Systems and Computer Engineering Technology and Science Inesc Tec Porto Portugal Faculty of Engineering University of Porto Department of Engineering Physics Portugal University Fernando Pessoa Faculty of Health Sciences R. Carlos da Maia 296 Porto4200-150 Portugal

This work presents an implementation of a reference optical cavity based on parasitic cavities on a low coherence interferometric system. This method allows a maximization of the number of sensors to be implemented wi... 详细信息

ISBN: (纸本)9798350361957

关键词： Optical fibers

Semi-empirical models of electron beam control in radiation technologies 2

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Semi-empirical models of electron beam control in radiation ...

2nd IEEE International Maghreb Meeting of the Conference on sciences and Techniques of Automatic Control and computer Engineering, MI-STA 2022

作者： Lazurik, Valentina Sawan, Salah Lazurik, Valentin Rudychev, Vladimir Kharkiv National University Computer Science Faculty Kharkiv Ukraine Tripoli University Engineering Faculty Tripoli Libya Kharkiv National University Physics and Technology Faculty Kharkiv Ukraine

ISBN: (数字)9781665479189

ISBN: (纸本)9781665479189

The work is devoted to the development of semi-empirical models for describing the depth-dose distribution in the layer depending on the angle of incidence of the electron beam. A geometric model of the region of energy transfer from an individual electron to a layer of matter with small effective values of charge and atomic number is proposed. Relationships are obtained in the form of integral transformations of the depth-dose distribution at normal incidence of the electron beam on the layer, which make it possible to calculate the depth-dose distribution for different angles of incidence of electrons. Algorithms were developed and software was implemented to determine the depth-dose distribution at various angles of incidence of the electron beam on the layer. A series of computer experiments on modeling depth dose distributions in a layer at different angles of incidence of electron beams was performed in a detailed physical model using the Monte Carlo method. Comparison of the results of calculations obtained within the framework of the proposed model with the results of modeling by the Monte Carlo method made it possible to determine the empirical parameters of the model and to estimate the range of applicability of the developed semi-empirical model. The possibilities of expanding the range of applicability of the developed semi-empirical model by modifying the geometric models of energy transfer from an individual electron to a layer of matter are discussed. © 2022 IEEE.

关键词： Electron beams

KNOWM Memristors in a Bridge Synapse delay-based Reservoir Computing system for detection of epileptic seizures

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arXiv 2025年

作者： Przyczyna, Dawid Hess, Grzegorz Szacilowski, Konrad AGH University of Science and Technology Academic Centre for Materials and Nanotechnology al. Mickiewicza 30 Kraków30-059 Poland AGH University of Science and Technology Faculty of Physics and Applied Computer Science al. Mickiewicza 30 Kraków30-059 Poland Jagiellonian University Department of Neurophysiology and Chronobiology Institute of Zoology and Biomedical Research ul. Gronostajowa 9 Kraków30-387 Poland

Nanodevices that show the potential for non-linear transformation of electrical signals and various forms of memory can be successfully used in new computational paradigms, such as neuromorphic or reservoir computing (RC). Dedicated hardware implementations based on functional neuromorphic structures significantly reduce energy consumption and/or increase computational capabilities of a given artificial neural network system. Concepts of RC, which as a flexible computational paradigm can be highly inclusive, are often used as a model to describe computations performed in materia. With mostly fixed internal structure, solid-state devices, especially memristors, are studied as computational substrates in various RC systems. In this work, we present single-node Echo State Machine (SNESM) RC system based on bridge synapse as a computational substrate (consisting of 4 memristors and a differential amplifier) used for epileptic seizure detection. KNOWM memristors were posed as ideal candidates because of their easy prototyping and reliability of operation. In this account, we present an application of commercially available KNOWM memristors in various neuromorphic applications, from simple analysis of switching and internal dynamics (elucidated form noise spectroscopy and total harmonic distortion analysis) to the classification and recognition of complex time series: epilepsy seizure recognition using a wrist-worn triaxial accelerometer. The results show that the evolution of the signal in a feedback loop helps improve the classification accuracy of the system for that task. The transformation in SNESM changes the correlation and distribution of the complexity parameters of the input signal. In general, there are more differences in the correlation of complexity parameters between the transformed signal and the input signal, which may explain the improvement in the classification scores. SNESM could prove to be a useful time series signal processing system designed to im

关键词： Differential amplifiers

Electronic structure, electron-phonon coupling, and superconductivity in noncentrosymmetric ThCoC2 from ab initio calculations

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Physical Review B 2021年第9期104卷 094502-094502页

作者： Gabriel Kuderowicz Paweł Wójcik Bartlomiej Wiendlocha Faculty of Physics and Applied Computer Science AGH University of Science and Technology Aleja Mickiewicza 30 Krakow 30-059 Poland

Superconductors without inversion symmetry in their crystal structure are known to exhibit unconventional properties. Recently, based on the measured temperature dependence of the magnetic field penetration depth, superconductivity in noncentrosymmetric ThCoC2 was proposed to be a nodal d wave and mediated by the spin fluctuations. Moreover, a non-BCS behavior of the temperature dependence of the electronic specific heat and the magnetic upper critical field were reported. In this work, the electronic structure, phonons, and electron-phonon coupling are studied in ThCoC2 on the basis of ab initio computations. The effect of the spin-orbit coupling on the electronic structure and electron-phonon interaction is analyzed, and a large splitting of the electronic band structure is found. The calculated electron-phonon coupling constant λ=0.59 remains in decent agreement with the experimental estimates, suggesting that the electron-phonon interaction is strong enough to explain superconductivity with Tc≃2.5 K. Nevertheless, we show that the conventional isotropic Eliashberg formalism is unable to describe the thermodynamic properties of the superconducting state, as calculated temperature dependence of the electronic specific heat and magnetic penetration depth deviate from experiments, which is likely driven by the strong spin-orbit coupling and inversion symmetry breaking. In addition, to shed more light on the pairing mechanism, we propose to measure the carbon isotope effect, as our calculations based on the electron-phonon coupling predict the observation of the isotope effect with an exponent α≃0.15.

关键词： Electron-phonon coupling Spin-orbit coupling Superconductivity Noncentrosymmetric materials Density functional calculations

Finite-size Catalysis in Quantum Resource Theories

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arXiv 2024年

作者： Lipka-Bartosik, Patryk Korzekwa, Kamil Department of Applied Physics University of Geneva Geneva1211 Switzerland Faculty of Physics Astronomy and Applied Computer Science Jagiellonian University Kraków30-348 Poland

Quantum catalysis, the ability to enable previously impossible transformations by using auxiliary systems without degrading them, has emerged as a powerful tool in various resource theories. Although catalytically enabled state transformations have been formally characterized by the monotonic behaviour of entropic quantifiers (e.g., the von Neumann entropy or non-equilibrium free energy), such characterizations often rely on unphysical assumptions, namely the ability of using catalysts of infinitely large dimension. This approach offers very limited insights into the practical significance of using catalysis for quantum information processing. Here, we address this problem across a broad class of quantum resource theories. Leveraging quantum information tools beyond the asymptotic regime, we establish sufficient conditions for the existence of catalytic transformations with finite-size catalysts. We further unveil connections between finite-size catalysis and multi-copy transformations. Notably, we discover a fascinating phenomenon of catalytic resonance: by carefully tailoring the catalysts’s state, one can drastically reduce the required dimension of the catalyst, thus enabling efficient catalytic transformations with minimal resources. Finally, we illustrate our findings with examples from the resource theories of entanglement and thermodynamics, as well in the context of catalytic unitary transformations. Copyright © 2024, The Authors. All rights reserved.

关键词： Catalysis

J-PET DETECTOR APPROACH FOR TESTING CP SYMMETRY IN THE ORTHO-POSITRONIUM ANNIHILATION

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Acta Physica Polonica B, Proceedings Supplement

Acta Physica Polonica B, Proceedings Supplement 2024年第1期17卷 1A11-1A111页

作者： Eliyan, Kavya V. Skurzok, Magdalena Moskal, Pawel Faculty of Physics Astronomy and Applied Computer Science Jagiellonian University Center for Theranostics Jagiellonian University Lojasiewicza 11 Kraków30-348 Poland

Positronium is a suitable leptonic system to test Charge-Parity (CP) discrete symmetry involving the correlations of photons momenta originating from ortho-positronium (o-Ps) annihilation. The photon–photon interaction in the final state due to the vacuum polarization may mimic CP symmetry violation of the order of 10−9, while weak interaction effects lead to a violation of the order of 10−14 according to the Standard Model prediction. So far, the experimental limits on CP symmetry violation in the o-Ps decay are set at the level of 10−4. One of the unique features of the J-PET detector is its ability to measure the polarization direction of the annihilation photons without the magnetic field. The J-PET detector can be used to explore discrete symmetry by looking for probable non-zero expectation values of the symmetry-odd operators, constructed from spin of ortho-Positronium and momentum, and polarization vectors of gamma (γ) quanta resulting from o-Ps annihilation. In this work, the J-PET detector experimental and analysis method to improve the sensitivity level at least by one order for CP discrete symmetry studies in the o-Ps decay via symmetry odd operator (ϵ⃗i·k⃗j), where ϵ⃗i and k⃗j are reconstructed polarization and momentum vectors of photons from the o-Ps decays, respectively, will be presented. © 2024 Jagiellonian university. All rights reserved.

关键词： Photons

Permanent Magnet Cogging Motor, from Concept to Prototype

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Permanent Magnet Cogging Motor, from Concept to Prototype

International Conference on Electrical Machines, ICEM

作者： Tomasz Lerch Szczepan Milewski Michał Drewniak Krzysztof Łukawski Tomasz Kołacz Faculty of Electrical Engineering Automatics Computer Science and Biomedical Engineering AGH University of Krakow Krakow Poland Polytechnic Faculty University of Applied Sciences in Tarnow Tarnów Poland

ISBN: (数字)9798350370607

ISBN: (纸本)9798350370614

This article presents a description of research that has led to the development of a new design permanent magnet machine. The machine is based on the operational principle of the transverse-flux machine (TFM). In the proposed solution, a core commonly used in radial flux machines was employed, significantly simplifying the construction of the TFM machine. This simultaneously reduces flux leakage and enhances the value of the developed electromagnetic torque. The article sequentially outlines the stages of research on the new design, ranging from analytical calculations through Finite Element Method (FEM) simulation to the construction of a machine prototype.

关键词： Permanent magnet machines Forging Stator cores Torque Windings Prototypes Motors Permanent magnets Finite element analysis Resistance heating