cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Efficient DMFT impurity solver using real-time dynamics with Matrix Product States
Creators: name: Ganahl, Martin
name: Aichhorn, Markus
name: Thunström, Patrik
name: Held, Karsten
name: Evertz, Hans Gerd
name: Verstraete, Frank
Publisher: name: arXiv
Year: 2014
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We propose to calculate spectral functions of quantum impurity models using the Time Evolving Block Decimation (TEBD) for Matrix Product States. The resolution of the spectral function is improved by a so-called linear prediction approach. We apply the method as an impurity solver within the Dynamical Mean Field Theory (DMFT) for the single- and two-band Hubbard model on the Bethe lattice. For the single-band model we observe sharp features at the inner edges of the Hubbard bands. A finite size scaling shows that they remain present in the thermodynamic limit. We analyze the real time-dependence of the double occupation after adding a single electron and observe oscillations at the same energy as the sharp feature in the Hubbard band, indicating a long-lived coherent superposition of states that correspond to the Kondo peak and the side peaks. For a two-band Hubbard model we observe an even richer structure in the Hubbard bands, which cannot be related to a multiplet structure of the impurity, in addition to sharp excitations at the band edges of a type similar to the single-band case.
description: 14 figures, 12 + pages including appendix. New Fig. 4b, Fig. 6, Fig.10, Fig.11 and Fig.A4
Markov processes related to the stationary measure for the open KPZ equation
Creators: name: Bryc, Wlodek
name: Kuznetsov, Alexey
name: Wang, Yizao
name: Wesolowski, Jacek
Publisher: name: arXiv
Year: 2021
Subjects: subject: Probability (math.PR)
subject: FOS: Mathematics
subject: 60J25, 44A15, 34L10

description: We provide a probabilistic description of the stationary measures for the open KPZ on the spatial interval $[0,1]$ in terms of a Markov process $Y$, which is a Doob's $h$ transform of the Brownian motion killed at an exponential rate. Our work builds on a recent formula of Corwin and Knizel which expresses the multipoint Laplace transform of the stationary solution of the open KPZ in terms of another Markov process $\mathbb T$: the continuous dual Hahn process with Laplace variables taking on the role of time-points in the process. The core of our approach is to prove that the Laplace transforms of the finite dimensional distributions of $Y$ and $\mathbb T$ are equal when the time parameters of one process become the Laplace variables of the other process and vice versa.
description: Expanded version, typo in (6.6) corrected
Scientometric engineering: Exploring citation dynamics via arXiv eprints
Creators: name: Okamura, Keisuke
Publisher: name: arXiv
Year: 2021
Subjects: subject: Digital Libraries (cs.DL)
subject: Computers and Society (cs.CY)
subject: Social and Information Networks (cs.SI)
subject: Physics and Society (physics.soc-ph)
subject: Applications (stat.AP)
subject: FOS: Computer and information sciences
subject: FOS: Physical sciences

description: Scholarly communications have been rapidly integrated into digitised and networked open ecosystems, where preprint servers have played a pivotal role in accelerating the knowledge transfer processes. However, quantitative evidence is scarce regarding how this paradigm shift beyond the traditional journal publication system has affected the dynamics of collective attention on science. To address this issue, we investigate the citation data of more than 1.5 million eprints on arXiv (https://arxiv.org/) and analyse the long-term citation trend for each discipline involved. We find that the typical growth and obsolescence patterns vary across disciplines, reflecting different publication and communication practices. The results provide unique evidence on the attention dynamics shaped by the research community today, including the dramatic growth and fast obsolescence of Computer Science eprints, which has not been captured in previous studies relying on the citation data of journal papers. Subsequently, we develop a quantitatively-and-temporally normalised citation index with an approximately normal distribution, which is useful for comparing citational attention across disciplines and time periods. Further, we derive a stochastic model consistent with the observed quantitative and temporal characteristics of citation growth and obsolescence. The findings and the developed framework open a new avenue for understanding the nature of citation dynamics.
description: [v1] 1+25 pages, 6 figures for main text; 1+24 pages, 14 figures for supplementary information. [v2] Revised version to appear in Quantitative Science Studies; 2+25 pages, 6 figures for main text; 25 pages, 14 figures for supplementary materials
Demonstration of New Cr aluminides and production as coupons for WP4 testing
Creators: name: Blackburn, Tom
name: Ma, Kan
name: Knowles, Sandy
name: Kerbstadt, Michael
name: Galetz, Mathias
name: Pinomaa, Tatu
name: Hernandez, Pascual Rebeca
name: Serrano, Marta
name: Van den Bergh, Krista
Publisher: name: Zenodo
Year: 2022

description: Chromium-based superalloys are a desirable candidate material for the heat exchanger in the next generation of concentrated solar power (CSP). Chromium alloys appear to bear greater thermal stability over alternative high temperature materials such as nickel superalloys, cobalt superalloys and ferritic superalloys. Additionally, iron additions increase the hardness or the alloys and reduce age softening over their ternary alloy equivalent. Preliminary oxidation results show improved oxidation resistance of these alloys.
Measurement of Ratios of $ν_μ$ Charged-Current Cross Sections on C, Fe, and Pb to CH at Neutrino Energies 2-20 GeV
Creators: name: Tice, B. G.
name: Datta, M.
name: Mousseau, J.
name: Aliaga, L.
name: Altinok, O.
name: Sazo, M. G. Barrios
name: Betancourt, M.
name: Bodek, A.
name: Bravar, A.
name: Brooks, W. K.
name: Budd, H.
name: Bustamante, M. J.
name: Butkevich, A.
name: Caicedo, D. A. Martinez
name: Castromonte, C. M.
name: Christy, M. E.
name: Chvojka, J.
name: da Motta, H.
name: Devan, J.
name: Dytman, S. A.
name: Díaz, G. A.
name: Eberly, B.
name: Felix, J.
name: Fields, L.
name: Fiorentini, G. A.
name: Gago, A. M.
name: Gallagher, H.
name: Gran, R.
name: Harris, D. A.
name: Higuera, A.
name: Hurtado, K.
name: Jerkins, M.
name: Kafka, T.
name: Kordosky, M.
name: Kulagin, S. A.
name: Le, T.
name: Maggi, G.
name: Maher, E.
name: Manly, S.
name: Mann, W. A.
name: Marshall, C. M.
name: Mari, C. Martin
name: McFarland, K. S.
name: McGivern, C. L.
name: McGowan, A. M.
name: Miller, J.
name: Mislivec, A.
name: Morfín, J. G.
name: Muhlbeier, T.
name: Naples, D.
name: Nelson, J. K.
name: Norrick, A.
name: Osta, J.
name: Palomino, J. L.
name: Paolone, V.
name: Park, J.
name: Patrick, C. E.
name: Perdue, G. N.
name: Rakotondravohitra, L.
name: Ransome, R. D.
name: Ray, H.
name: Ren, L.
name: Rodrigues, P. A.
name: Savage, D. G.
name: Schellman, H.
name: Schmitz, D. W.
name: Simon, C.
name: Snider, F. D.
name: Salinas, C. J. Solano
name: Tagg, N.
name: Valencia, E.
name: Velásquez, J. P.
name: Walton, T.
name: Wolcott, J.
name: Zavala, G.
name: Zhang, D.
name: Ziemer, B. P.
Publisher: name: arXiv
Year: 2014
Subjects: subject: High Energy Physics - Experiment (hep-ex)
subject: Nuclear Experiment (nucl-ex)
subject: FOS: Physical sciences

description: We present measurements of $ν_μ$ charged-current cross section ratios on carbon, iron, and lead relative to a scintillator (CH) using the fine-grained MINERvA detector exposed to the NuMI neutrino beam at Fermilab. The measurements utilize events of energies $2=8~GeV$, which have a reconstructed $μ^{-}$ scattering angle less than $17^\circ$ to extract ratios of inclusive total cross sections as a function of neutrino energy $E_ν$ and flux-integrated differential cross sections with respect to the Bjorken scaling variable $x$. These results provide the first high-statistics direct measurements of nuclear effects in neutrino scattering using different targets in the same neutrino beam. Measured cross section ratios exhibit a relative depletion at low $x$ and enhancement at large $x$. Both become more pronounced as the nucleon number of the target nucleus increases. The data are not reproduced by GENIE, a conventional neutrino-nucleus scattering simulation, or by the alternative models for the nuclear dependence of inelastic scattering that are considered.
description: 6 pages, 2 figures, 7 pages of supplemental material. Published in Physical Review Letters June 13, 2014
Between an $n$-ary and an $n{+}1$-ary near-unanimity term
Creators: name: Lipparini, Paolo
Publisher: name: arXiv
Year: 2021
Subjects: subject: Rings and Algebras (math.RA)
subject: FOS: Mathematics
subject: 08B10, 08B05, 06B75, 06E75

description: We devise a condition strictly between the existence of an $n$-ary and an $n{+}1$-ary near-unanimity term. We evaluate exactly the distributivity and modularity levels implied by such a condition.
description: v. 2, a few fixes, a few additions
An Examination of Hardiness Throughout the Sport Injury Process
Creators: name: Wadey, Ross Gordon
Publisher: name: Cardiff Metropolitan University
Year: 2022
Subjects: Sports science and exercise not elsewhere classified

description: This thesis examined hardiness throughout the sport injury process. Study 1 investigated the affect of hardiness on the prediction of, and response to, sport injury. The data were analysed using hierarchical logistic regression and a two-way multivariate analysis of variance. Findings revealed that negative major life events predicted sport injury and hardiness moderated this relationship. Furthermore, main effects were found for hardiness and time on injured athletes’ psychological responses and use of coping strategies. But despite these significant findings, this study was limited in that it failed to explain why these phenomena occurred. As a result, Study 2 aimed to enhance the interpretability and meaningfulness of the findings from Study 1. Semi-structured interviews were conducted and transcribed, which were then analysed and displayed using composite sequence analysis. Findings revealed that athletes high in hardiness were less susceptible to injury as a result of negative major life events and were able to facilitate their recovery from injury because they used a refined repertoire of problem- and emotion-focused coping strategies. In contrast, athletes low in hardiness exacerbated the impact of negative major life events and injury by using avoidance coping strategies. The depth of these findings offered implications for professional practice in terms of minimising rates of injury occurrence and facilitating recovery from injury. Study 3 aimed to evaluate a hardiness intervention throughout the sport injury process. Within the framework of action research proposed by Evans, Fleming, and Hardy (2000), multiple methods of data collection were used. Findings revealed that the pre-injury intervention increased non-injured athletes’ awareness of how to improve their practice when coping with negative major life events, whereas the post-injury intervention improved the practice of an injured athlete by facilitating his recovery. The thesis concludes with a discussion of its strengths and limitations, practical implications and future research directions.
Scattering theory for nonlinear Schroedinger equations with inverse-square potential
Creators: name: Zhang, Junyong
name: Zheng, Jiqiang
Publisher: name: arXiv
Year: 2013
Subjects: subject: Analysis of PDEs (math.AP)
subject: FOS: Mathematics
subject: 35P25, 35Q55

description: We study the long-time behavior of solutions to nonlinear Schroedinger equations with some critical rough potential of inverse square type. The new ingredients are the interaction Morawetz-type inequalities and Sobolev norm property associated with the Lapalacian with inverse square potential. We use such properties to obtain the scattering theory for the defocusing energy-subcritical nonlinear Schroedinger equation with inverse square potential in energy space.
description: 21pages
A minimal-variable symplectic integrator on spheres
Creators: name: McLachlan, Robert I.
name: Modin, Klas
name: Verdier, Olivier
Publisher: name: arXiv
Year: 2014
Subjects: subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences
subject: 37M15, 70H06, 70H08, 53Z05, 65L06

description: We construct a symplectic, globally defined, minimal-coordinate, equivariant integrator on products of 2-spheres. Examples of corresponding Hamiltonian systems, called spin systems, include the reduced free rigid body, the motion of point vortices on a sphere, and the classical Heisenberg spin chain, a spatial discretisation of the Landau-Lifschitz equation. The existence of such an integrator is remarkable, as the sphere is neither a vector space, nor a cotangent bundle, has no global coordinate chart, and its symplectic form is not even exact. Moreover, the formulation of the integrator is very simple, and resembles the geodesic midpoint method, although the latter is not symplectic.
A Data-Driven Approach to Coarse-Graining Simple Liquids in Confinement
Creators: name: Nadkarni, Ishan
name: Wu, Haiyi
name: Aluru, Narayana. R.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: We propose a data-driven framework for identifying coarse-grained (CG) Lennard-Jones (LJ) potential parameters in confined systems for simple liquids. Our approach involves the use of a Deep Neural Network (DNN) that is trained to approximate the solution of the Inverse Liquid State (ILST) problem for confined systems. The DNN model inherently incorporates essential physical characteristics specific to confined fluids, enabling accurate prediction of inhomogeneity effects. By utilizing transfer learning, we predict single-site LJ potentials of simple multiatomic liquids confined in a slit-like channel, which effectively replicate both the fluid structure and molecular force of the target All-Atom (AA) system when the electrostatic interactions are not dominant. In addition, we showcase the synergy between the data-driven approach and the well-known Bottom-Up coarse-graining method utilizing Relative-Entropy (RE) Minimization. Through sequential utilization of these two methods, the robustness of the iterative RE method is significantly augmented, leading to a remarkable enhancement in convergence.
description: Journal of Chemical Theory and Computation (2023)
Quantum spin liquid in an RKKY-coupled two-impurity Kondo system
Creators: name: Wójcik, Krzysztof P.
name: Kroha, Johann
Publisher: name: arXiv
Year: 2021
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: We consider a 2-impurity Kondo system with spin-exchange coupling within the conduction band. Our numerical renormalization group calculations show that for strong intraband spin correlations the competition of these correlations with Kondo spin screening stabilizes a metallic spin-liquid phase of the localized spins without geometric frustration. For weak Kondo coupling the spin liquid and the Kondo singlet phase are separated by two quantum phase transitions and an intermediate RKKY spin-dimer phase, while beyond a critical coupling they are connected by a crossover. The results suggest how a quantum spin liquid may be realized in heavy-fermion systems near a spin-density wave instability.
description: 6 pages, 4 figures
The Poincaré pear and Poincaré-Darwin fission theory in astrophysics, 1885-1901
Creators: name: Walter, Scott A.
Publisher: name: arXiv
Year: 2023
Subjects: subject: History and Philosophy of Physics (physics.hist-ph)
subject: FOS: Physical sciences
subject: 01A55 (Primary) 85-03 (Secondary)

description: In the early 1880s, Henri Poincaré discovered a new equilibrium figure for uniformly-rotating fluid masses -- the pear, or piriform figure -- and speculated that in certain circumstances the pear splits into two unequal parts, and provides thereby a model for the origin of binary stars. The contemporary emergence of photometric and spectroscopic studies of variable stars fueled the first models of eclipsing binaries, and provided empirical support for a realist view of equilibrium figures -- including the pear -- in the cosmic realm. The paper reviews astrophysical interpretation of the Poincaré pear and the Poincaré-Darwin fission hypothesis with respect to research on variable stars from 1885 to 1901.
Collection Development: A Holistic Approach
Creators: name: Kubilius, Ramune K.
Publisher: name: Galter Health Science Library & Learning Center
Year: 2017

description: Presentation in Graduate School of Library & Information Science class (LS780: Health Sciences Librarianship) at Dominican University, River Forest, IL on February 26, 2005. Guest presenter: Ramune K. Kubilius, co-presenter of this lecture, lead instructor of the course: Linda J. Walton. Lecture was derived from a half day continuing education course of the same name that was developed by the co-presenters and approved by the Medical Library Association in 2005/2006.
Order-preserving strong schemes for SDEs with locally Lipschitz coefficients
Creators: name: Zhang, Zhongqiang
name: Ma, Heping
Publisher: name: arXiv
Year: 2014
Subjects: subject: Numerical Analysis (math.NA)
subject: FOS: Mathematics
subject: Primary 60H35, secondary 65C30, 60H10

description: We introduce a class of explicit balanced schemes for stochastic differential equations with coefficients of superlinearly growth satisfying a global monotone condition. The first scheme is a balanced Euler scheme and is of order half in the mean-square sense whereas it is of order one under additive noise. The second scheme is a balanced Milstein scheme, which is of order one in the mean-square sense. Some numerical results are presented.
Tight Bounds for Symmetric Divergence Measures and a Refined Bound for Lossless Source Coding
Creators: name: Sason, Igal
Publisher: name: arXiv
Year: 2014
Subjects: subject: Information Theory (cs.IT)
subject: Probability (math.PR)
subject: FOS: Computer and information sciences
subject: FOS: Mathematics

description: Tight bounds for several symmetric divergence measures are derived in terms of the total variation distance. It is shown that each of these bounds is attained by a pair of 2 or 3-element probability distributions. An application of these bounds for lossless source coding is provided, refining and improving a certain bound by Csiszár. Another application of these bounds has been recently introduced by Yardi. et al. for channel-code detection.
description: Appears in the IEEE Trans. on Information Theory, February 2015. arXiv admin note: substantial text overlap with arXiv:1502.06428
MMT: A Multilingual and Multi-Topic Indian Social Media Dataset
Creators: name: Dalal, Dwip
name: Srivastava, Vivek
name: Singh, Mayank
Publisher: name: arXiv
Year: 2023
Subjects: subject: Computation and Language (cs.CL)
subject: Machine Learning (cs.LG)
subject: Social and Information Networks (cs.SI)
subject: FOS: Computer and information sciences

description: Social media plays a significant role in cross-cultural communication. A vast amount of this occurs in code-mixed and multilingual form, posing a significant challenge to Natural Language Processing (NLP) tools for processing such information, like language identification, topic modeling, and named-entity recognition. To address this, we introduce a large-scale multilingual, and multi-topic dataset (MMT) collected from Twitter (1.7 million Tweets), encompassing 13 coarse-grained and 63 fine-grained topics in the Indian context. We further annotate a subset of 5,346 tweets from the MMT dataset with various Indian languages and their code-mixed counterparts. Also, we demonstrate that the currently existing tools fail to capture the linguistic diversity in MMT on two downstream tasks, i.e., topic modeling and language identification. To facilitate future research, we will make the anonymized and annotated dataset available in the public domain.
Préambule
Creators: name: Margaillan, Cathy
Publisher: name: Classiques Garnier
Year: 2023
Subjects: subject: Littérature féminine
subject: Avant-garde
subject: Arts visuels
subject: Théosophie
subject: Philosophie
subject: Réception critique
subject: Musique
subject: Poésie
subject: Théâtre expérimental
subject: Ésotérisme

description: Ce préambule explique que ce volume critique sur Benedetta Cappa Marinetti s’avère à la fois l’aboutissement et le tremplin du travail de recherche sur Benedetta Cappa Marinetti et ses œuvres et il souligne les raisons de faire connaître notre auteure et ses créations en France.
Linear solvers for power grid optimization problems: a review of GPU-accelerated linear solvers
Creators: name: Swirydowicz, Kasia
name: Darve, Eric
name: Jones, Wesley
name: Maack, Jonathan
name: Regev, Shaked
name: Saunders, Michael A.
name: Thomas, Stephen J.
name: Peles, Slaven
Publisher: name: arXiv
Year: 2021
Subjects: subject: Numerical Analysis (math.NA)
subject: Mathematical Software (cs.MS)
subject: FOS: Mathematics
subject: FOS: Computer and information sciences

description: The linear equations that arise in interior methods for constrained optimization are sparse symmetric indefinite and become extremely ill-conditioned as the interior method converges. These linear systems present a challenge for existing solver frameworks based on sparse LU or LDL^T decompositions. We benchmark five well known direct linear solver packages using matrices extracted from power grid optimization problems. The achieved solution accuracy varies greatly among the packages. None of the tested packages delivers significant GPU acceleration for our test cases.
New one shot quantum protocols with application to communication complexity
Creators: name: Anshu, Anurag
name: Jain, Rahul
name: Mukhopadhyay, Priyanka
name: Shayeghi, Ala
name: Yao, Penghui
Publisher: name: arXiv
Year: 2014
Subjects: subject: Quantum Physics (quant-ph)
subject: Computational Complexity (cs.CC)
subject: Information Theory (cs.IT)
subject: FOS: Physical sciences
subject: FOS: Computer and information sciences

description: In this paper we present the following quantum compression protocol: P : Let $ρ,σ$ be quantum states such that $S(ρ|| σ) = \text{Tr} (ρ\log ρ- ρ\log σ)$, the relative entropy between $ρ$ and $σ$, is finite. Alice gets to know the eigen-decomposition of $ρ$. Bob gets to know the eigen-decomposition of $σ$. Both Alice and Bob know $S(ρ|| σ)$ and an error parameter $ε$. Alice and Bob use shared entanglement and after communication of $\mathcal{O}((S(ρ|| σ)+1)/ε^4)$ bits from Alice to Bob, Bob ends up with a quantum state $\tildeρ$ such that $F(ρ, \tildeρ) \geq 1 - 5ε$, where $F(\cdot)$ represents fidelity. This result can be considered as a non-commutative generalization of a result due to Braverman and Rao [2011] where they considered the special case when $ρ$ and $σ$ are classical probability distributions (or commute with each other) and use shared randomness instead of shared entanglement. We use P to obtain an alternate proof of a direct-sum result for entanglement assisted quantum one-way communication complexity for all relations, which was first shown by Jain, Radhakrishnan and Sen [2005,2008]. We also present a variant of protocol P in which Bob has some side information about the state with Alice. We show that in such a case, the amount of communication can be further reduced, based on the side information that Bob has. Our second result provides a quantum analogue of the widely used classical correlated-sampling protocol. For example, Holenstein [2007] used the classical correlated-sampling protocol in his proof of a parallel-repetition theorem for two-player one-round games.
description: 23 pages. Changed title, abstract and presentation of the paper
Covert Cognizance: Embedded Intelligence for Industrial Systems
Creators: name: Sundaram, Arvind
Publisher: name: Purdue University Graduate School
Year: 2022
Subjects: Nuclear engineering (incl. fuel enrichment and waste processing and storage)
Cyberphysical systems and internet of things

description: Can a critical industrial system, such as a nuclear reactor, be made self-aware and cognizant of its operational history? Can it alert authorities covertly to malicious intrusion without exposing its defense mechanisms? What if the intruders are highly knowledgeable adversaries, or even insiders that may have designed the system? This thesis addresses these research questions through a novel physical process defense called Covert Cognizance (C2). C2 serves as a last line of defense to industrial systems when existing information and operational technology defenses have been breached by advanced persistent threat (APT) actors or insiders. It is an active form of defense that may be embedded in an existing system to induce intelligence, i.e., self-awareness, and make various subsystems aware of each other. It interacts with the system at the process level and provides an additional layer of security to the process data therein without the need of a human in the loop. The C2 paradigm is founded on two core requirements – zero-impact and zero-observability. Departing from contemporary active defenses, zero-impact requires a successful implementationto leave no footprint on the system ensuring identical operation while zero-observability requires that the embedding is immune to pattern-discovery algorithms. In other words, a third-party such as a malicious intruder must be unable to detect the presence of the C2 defense based on observation of the process data, even when augmented by machine learning tools that are adept at pattern discovery. In the present work, nuclear reactor simulations are embedded with the C2 defense to induce awareness across subsystems and defend them against highly knowledgeable adversaries that have bypassed existing safeguards such as model-based defenses. Specifically, the subsystems are made aware of each other by embedding critical information from the process variables of one sub-module along the noise of the process variables of another, thus rendering the implementation covert and immune to pattern discovery. The implementation is validated using generative adversarial nets, representing a state-of-the-art machine learning tool, and statistical analysis of the reactor states, control inputs, outputs etc. The work is also extended to data masking applications via the deceptive infusion of data (DIOD) paradigm. Future work focuses on the development of automated C2 modules for “plug ‘n’ play” deployment onto critical infrastructure and/or their digital twins.
The Steinberg representation is irreducible
Creators: name: Putman, Andrew
name: Snowden, Andrew
Publisher: name: arXiv
Year: 2021
Subjects: subject: Representation Theory (math.RT)
subject: Group Theory (math.GR)
subject: FOS: Mathematics

description: We prove that the Steinberg representation of a connected reductive group over an infinite field is irreducible. For finite fields, this is a classical theorem of Steinberg and Curtis.
description: 28 pages, major revision, to appear in Duke Math. J
Derivation of the magnetic Euler-Heisenberg energy
Creators: name: Gravejat, Philippe
name: Lewin, Mathieu
name: Séré, Éric
Publisher: name: arXiv
Year: 2016
Subjects: subject: Mathematical Physics (math-ph)
subject: Analysis of PDEs (math.AP)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences
subject: FOS: Mathematics

description: In quantum field theory, the vacuum is a fluctuating medium which behaves as a nonlinear polarizable material. In this article, we perform the first rigorous derivation of the magnetic Euler-Heisenberg effective energy, a nonlinear functional that describes the effective fluctuations of the quantum vacuum in a classical magnetic field. We start from a classical magnetic field in interaction with a quan-tized Dirac field in its ground state, and we study a limit in which the classical magnetic field is slowly varying. After a change of scales, this is equivalent to a semi-classical limit $\hbar\to0$, with a strong magnetic field of order $1/\hbar$. In this regime, we prove that the energy of Dirac's polarized vacuum converges to the Euler-Heisenberg functional. The model has ultraviolet divergences, which we regularize using the Pauli-Villars method. We also discuss how to remove the regularization of the Euler-Heisenberg effective Lagrangian, using charge renormaliza-tion, perturbatively to any order of the coupling constant.
description: Final version to appear in J. Math. Pure Appl
Partial Density of States Ligand Field Theory (PDOS-LFT): Recovering a LFT-Like Picture and Application to Photoproperties of Ruthenium(II) Polypyridine Complexes
Creators: name: Magero, Denis
name: Casida, Mark E.
name: Amolo, George
name: Makau, Nicholas
name: Kituyi, Lusweti
Publisher: name: arXiv
Year: 2017
Subjects: subject: Chemical Physics (physics.chem-ph)
subject: FOS: Physical sciences

description: Gas phase density-functional theory (DFT) and time-dependent DFT (TD-DFT) calculations are reported for a data base of 98 ruthenium(II) polypyridine complexes. Comparison with X-ray crystal geometries and with experimental absorption spectra measured in solution show an excellent linear correlation with the results of the gas phase calculations. Comparing this with the usual chemical understanding based upon ligand field theory (LFT) is complicated by the large number of molecular orbitals present and especially by the heavy mixing of the antibonding metal e*$_{g}$ orbitals with ligand orbitals. Nevertheless, we show that a deeper understanding can be obtained by a partial density-of-states (PDOS) analysis which allows us to extract approximate metal t$_{2g}$ and e*$_{g}$ and ligand π* orbital energies in a well-defined way, thus providing a PDOS analogue of LFT (PDOS-LFT). Not only do PDOS-LFT energies generate a spectrochemical series for the ligands, but orbital energy differences provide good estimates of TD-DFT absorption energies. Encouraged by this success, we use frontier-molecular-orbital-theory-like reasoning to construct a model which allows us in most, but not all, of the cases studied to use PDOS-LFT energies to provide a semiquantitative relationship between luminescence lifetimes at room temperature and liquid nitrogen temperature.
Description of ion motion in a Paul trap immersed in a cold atomic gas
Creators: name: Krych, Michał
name: Idziaszek, Zbigniew
Publisher: name: arXiv
Year: 2013
Subjects: subject: Quantum Gases (cond-mat.quant-gas)
subject: Atomic Physics (physics.atom-ph)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We investigate the problem of a single ion in a radio-frequency trap and immersed in an ultracold Bose gas either in a condensed or a non-condensed phase. We develop master equation formalism describing the sympathetic cooling and we determine the cooling rates of ions. We show that cold atomic reservoir modifies the stability diagram of the ion in the Paul trap creating the regions where the ion is either cooled or heated due to the energy quanta exchanged with the time-dependent potential.
description: 11 pages, 4 figures, extended and substantially revised version of the article
A López-Escobar theorem for metric structures, and the topological Vaught conjecture
Creators: name: Coskey, Samuel
name: Lupini, Martino
Publisher: name: arXiv
Year: 2014
Subjects: subject: Logic (math.LO)
subject: FOS: Mathematics
subject: Primary 03C95, 03E15, Secondary 54E50

description: We show that a version of López-Escobar's theorem holds in the setting of logic for metric structures. More precisely, let $\mathbb{U}$ denote the Urysohn sphere and let $\mathrm{Mod}(\mathcal{L},\mathbb{U})$ be the space of metric $\mathcal{L}$-structures supported on $\mathbb{U}$. Then for any $\mathrm{Iso}(\mathbb{U})$-invariant Borel function $f\colon \mathrm{Mod}(\mathcal{L}, \mathbb{U})\rightarrow \lbrack 0,1]$, there exists a sentence $ϕ$ of $\mathcal{L}_{ω_{1}ω}$ such that for all $M\in \mathrm{Mod}(\mathcal{L},\mathbb{U})$ we have $f(M)=ϕ^{M}$. At the same time we introduce a variant $\mathcal{L}_{ω_1ω}^\ast$ of $\mathcal{L}_{ω_1ω}$ in which the usual quantifiers are replaced with category quantifiers, and establish the analogous theorem for $\mathcal{L}_{ω_1ω}^\ast$. This answers a question of Ivanov and Majcher-Iwanow. We prove several consequences, for example every orbit equivalence relation of a Polish group action is Borel isomorphic to the isomorphism relation on the set of models of a given $\mathcal{L}_{ω_{1}ω}$-sentence that are supported on the Urysohn sphere. This in turn provides a model-theoretic reformulation of the topological Vaught conjecture.
description: 17 pages
Dirac-Coulomb operators with general charge distribution. I. Distinguished extension and min-max formulas
Creators: name: Esteban, Maria J.
name: Lewin, Mathieu
name: Séré, Éric
Publisher: name: arXiv
Year: 2020
Subjects: subject: Spectral Theory (math.SP)
subject: Mathematical Physics (math-ph)
subject: Analysis of PDEs (math.AP)
subject: FOS: Mathematics
subject: FOS: Physical sciences

description: This paper is the first of a series where we study the spectral properties of Dirac operators with the Coulomb potential generated by any finite signed charge distribution $μ$. We show here that the operator has a unique distinguished self-adjoint extension under the sole condition that $μ$ has no atom of weight larger than or equal to one. Then we discuss the case of a positive measure and characterize the domain using a quadratic form associated with the upper spinor, following earlier works by Esteban and Loss. This allows us to provide min-max formulas for the eigenvalues in the gap. In the event that some eigenvalues have dived into the negative continuum, the min-max formulas remain valid for the remaining ones. At the end of the paper we also discuss the case of multi-center Dirac-Coulomb operators corresponding to $μ$ being a finite sum of deltas.
description: Final version to appear in Annales Henri Lebesgue
CERN InvenioRDM kickoff (Northwestern)
Creators: name: Holmes, Kristi
name: Carson, Matthew Brandon
Publisher: name: Galter Health Science Library & Learning Center
Year: 2019

description: Slides from the InvenioRDM kickoff at CERN. Each partner answered these questions. Northwestern participated remotely and presented these slides. Sponsored by Clinical and Translational Sciences Award (CTSA) Program, National Center for Data to Health (CD2H), Galter Health Sciences Library & Learning Center, Northwestern University Clinical and Translational Sciences Institute (NUCATS)
Signal of doubly charged Higgs at $e^+e^-$ colliders
Creators: name: Hue, L. T.
name: Huong, D. T.
name: Long, H. N.
name: Hung, H. T.
name: Thao, N. H.
Publisher: name: arXiv
Year: 2014
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: Masses and signals of the production of Doubly charged Higgses(DCH) in the framework of the supersymmetric reduced minimal 3-3-1 model(SUSYRM331) are investigated. In the DCH sector, weprove that there always exists a region of the parameter space where the mass of the lightest DCH is in order of $\mathcal{O}(100)$ GeV even when all other new particles are very heavy.The lightest DCH mainly decays to two same-sign leptons while the dominated decay channels of the heavy DCHs are those decay to heavy particles. We analyze each production cross section for $e^+e^- \rightarrow H^{++} H^{--}$ as a function of a few kinematic variables, which are useful to discuss the creation of the DCHs in the $e^+e^-$ colliders as a signal of new physics beyond the Standard Model. The numerical study shows that the cross sections for creating the lightest DCH can reach values of few pbs. The two other DCHs are too heavy, beyond the observable range of experiments. The lightest DCH may be detected by the International Linear Collider (ILC) or the Compact LInear Collider (CLIC) by searching its decay to a same-sign charged lepton pair.
description: 48 pages, 22 figures, more considerations included, accepted for publication in PTEP
On the phase change for perturbations of Hamiltonian systems with separatrix crossing
Creators: name: Neishtadt, Anatoly
name: Okunev, Alexey
Publisher: name: arXiv
Year: 2020
Subjects: subject: Dynamical Systems (math.DS)
subject: FOS: Mathematics
subject: 34C29

description: We study the evolution of angular variable (phase) for general (not necessarily Hamiltonian) perturbations of Hamiltonian systems with one degree of freedom near separatrices of the unperturbed system. To this end, we use averaged system of order 2. We obtain estimates for the accuracy of order 2 averaged system near separatrices and use these estimates to prove a formula for the phase change when solutions of the perturbed system approach separatrices of the unperturbed system (such formula is known when the perturbation is Hamiltonian). As an application of this formula, we show that two natural definitions of probability of capture into different domains after separatrix crossing proposed by V.I. Arnold and D.V. Anosov lead to the same formula for this probability.
description: 34 pages, 2 figures. Minor changes, add journal reference
Accurate methods for the analysis of strong-drive effects in parametric gates
Creators: name: Petrescu, Alexandru
name: Calonnec, Camille Le
name: Leroux, Catherine
name: Di Paolo, Agustin
name: Mundada, Pranav
name: Sussman, Sara
name: Vrajitoarea, Andrei
name: Houck, Andrew A.
name: Blais, Alexandre
Publisher: name: arXiv
Year: 2021
Subjects: subject: Quantum Physics (quant-ph)
subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: The ability to perform fast, high-fidelity entangling gates is an important requirement for a viable quantum processor. In practice, achieving fast gates often comes with the penalty of strong-drive effects that are not captured by the rotating-wave approximation. These effects can be analyzed in simulations of the gate protocol, but those are computationally costly and often hide the physics at play. Here, we show how to efficiently extract gate parameters by directly solving a Floquet eigenproblem using exact numerics and a perturbative analytical approach. As an example application of this toolkit, we study the space of parametric gates generated between two fixed-frequency transmon qubits connected by a parametrically driven coupler. Our analytical treatment, based on time-dependent Schrieffer-Wolff perturbation theory, yields closed-form expressions for gate frequencies and spurious interactions, and is valid for strong drives. From these calculations, we identify optimal regimes of operation for different types of gates including $i$SWAP, controlled-Z, and CNOT. These analytical results are supplemented by numerical Floquet computations from which we directly extract drive-dependent gate parameters. This approach has a considerable computational advantage over full simulations of time evolutions. More generally, our combined analytical and numerical strategy allows us to characterize two-qubit gates involving parametrically driven interactions, and can be applied to gate optimization and cross-talk mitigation such as the cancellation of unwanted ZZ interactions in multi-qubit architectures.
description: 20 pages, 9 figures, 62 references
title: Surface color perception under different illuminants and surface collections
Creators: name: Arnold, Claus
Publisher: name: Universität Regensburg
Year: 2009
Subjects: subject: Farbkonstanz , Visuelle Wahrnehmung , Farbensehen , , color constancy
subject: 150 Psychologie

description: The human visual system is capable of maintaining constant object colors despite changes in the surrounding illumination. This is rather surprising since a change in illumination yields a change in the absorption rates of the retinal photoreceptors. This attribute of the visual system is called color constancy. There are different types of situations that are apparent in everyday life. In one situation illumination changes rather slowly. In a second situation there are multiple illuminants present within the scene. In a third situation illumination changes temporally abrupt, for instance, when the sun gets covered by a cloud. A series of four experiments is reported concerning the degree of of color constancy in this third situation. Using a discrimination paradigm, color constancy is investigated under different illuminant color changes and different surface collections. The results show best performance under greenish and bluish illuminants and surface collection and worst performance under reddish illuminants and surface collections. Two major results stand out: First, the results are comparable to those from studies regarding other color constancy situations. Second, performance under specific illuminants and surface collections seem to correlate with their occurrence in everyday life.
description: Das menschliche visuelle System ist in der Lage, trotz Veränderungen in der umgebenden Beleuchtung Objektfarben konstant zu halten. Dies ist ziemlich überraschend, da eine Veränderung der Beleuchtung zu einer Änderung der Absorptionsraten der retinalen Photorezeptoren führt. Diese Eigenschaft des visuellen Systems nennt man Farbkonstanz. Es gibt verschiedene Arten von Situationen, die im täglichen Leben auftreten. In einer Situation ändert sich die Beleuchtung langsam. In einer zweiten Situation sind mehrere Beleuchtung in einer Szene vorhanden. In einer dritten Situation Situation wechselt die Beleuchtung zeitlich abrupt, z. B. wenn die Sonne von einer Wolke verdeckt wird. Eine Reihe von vier Experimenten wird berichtet, die sich mit dem Ausmaß der Farbkonstanz in dieser dritten Situation beschäftigt. Farbkonstanz wird mit einem Diskriminationsparadigma unter verschiedenen Beleuchtungsfarbwechsel und Oberflächenkollektionen untersucht. Die Ergebnisse zeigen beste Leistung unter grünlichen und bläulichen Beleuchtungen und Oberflächenkollektionen und schwächste Leistung unter rötlichen Beleuchtungen und Oberflächenkollektionen. Zwei Hauptergebnisse fallen auf: Erstens, die Ergebnisse sind vergleichbar mit denen aus Studien, die andere Farbkonstanzsituationen untersuchen. Zweitens, die Leistung unter bestimmten Beleuchtungen und Oberflächenkollektionen scheinen mit der Häufigkeit ihres Vorkommens im täglichen Leben zu korrelieren.
¿De qué hablamos cuando hablamos de Humanidades Digitales?
Creators: name: del Rio, Gimena
Publisher: name: Zenodo
Year: 2014
Subjects: disciplinas
geopolítica
Humanidades Digitales
Ciencias Sociales

description: A pesar de que en muchos países las Humanidades Digitales son parte del currículo académico o bien se han incorporado como tema, tecnología aplicada o metodología en el ámbito universitario o de la investigación, nos encontramos lejos de un consenso global acerca de su definición. Por un lado, ciertas voces apuntan a la necesidad de ampliar las fronteras del término al fenómeno de la cultura digital (Alvarado, 2011; Manovich, 2013), mientras que otras mantienen su mirada centrada sobre el mundo scholar (Kirschenbaum, 2010). Esta multiplicidad de definiciones se ve aún más acentuada si nos recortamos sobre la geografía de las Humanidades Digitales, evidenciándose allí una brecha entre las investigaciones, proyectos y actividades llevados a cabo en el mundo de la Europa y América anglo y la hispana. Entendiendo que uno de los espacios más destacados para el intercambio académico es el de los congresos, este trabajo se propone tomar como objeto de estudio el contenido de los tres últimos grandes eventos académicos que buscan inscribirse desde su título en el campo de las Humanidades Digitales en España, México y Argentina, para dar cuenta de las similitudes y diferencias en las actividades, aproximaciones, temas y conceptos que en ellos se desarrollaron.
Asymptotic equivalence for regression under fractional noise
Creators: name: Schmidt-Hieber, Johannes
Publisher: name: arXiv
Year: 2013
Subjects: subject: Statistics Theory (math.ST)
subject: FOS: Mathematics

description: Consider estimation of the regression function based on a model with equidistant design and measurement errors generated from a fractional Gaussian noise process. In previous literature, this model has been heuristically linked to an experiment, where the anti-derivative of the regression function is continuously observed under additive perturbation by a fractional Brownian motion. Based on a reformulation of the problem using reproducing kernel Hilbert spaces, we derive abstract approximation conditions on function spaces under which asymptotic equivalence between these models can be established and show that the conditions are satisfied for certain Sobolev balls exceeding some minimal smoothness. Furthermore, we construct a sequence space representation and provide necessary conditions for asymptotic equivalence to hold.
description: Published in at http://dx.doi.org/10.1214/14-AOS1262 the Annals of Statistics (http://www.imstat.org/aos/) by the Institute of Mathematical Statistics (http://www.imstat.org)
title: The ideological origins of piracy in international legal thought.
Creators: name: Krever, Tor
Publisher: name: London School of Economics and Political Science (LSE)
Year: 2018
Subjects: subject: K Law (General)

description: This thesis explores the origins of the pirate in international legal thought. It takes as its starting point the recent wave of piracy off the coast of Somalia, mapping the image of the pirate constructed by contemporary legal commentators. The figure of the pirate that takes shape is the archetype of illegitimacy and epitome of enmity in international law: hostis humani generis. Where and when did this figure first emerge in international legal thought? My argument is twofold. First, against dominant transhistorical accounts which project the pirate backwards in an unbroken arc from the present to antiquity, I show that its juridical identity has been marked by fundamental discontinuities and transformations. Second, I locate the construction of a distinctly modern figure of the pirate in the emergence of a capitalist world economy in the long 16th century. The pirate’s universal enmity, I suggest, was initially religious in nature, an ideology rooted in inter-imperial rivalries confronting Habsburg Spain with Ottoman, in the Mediterranean, and Protestant, in the Atlantic, threats to a universalising Christendom. With the development of an early capitalist economy and the growing coincidence of imperial interests with trade, the image of the pirate began to change. In the work of Grotius, I argue, its enmity was transformed, the pirate rendered not as religious foe, but as enemy of a universal right to commerce. It is this new secular figure of enmity, the thesis concludes, that is produced and reproduced in modern legal thought.