cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Quantum Corrections in 4d N=1 Infinite Distance Limits and the Weak Gravity Conjecture
Creators: name: Klaewer, Daniel
name: Lee, Seung-Joo
name: Weigand, Timo
name: Wiesner, Max
Publisher: name: arXiv
Year: 2020
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We study quantum corrections in four-dimensional theories with $N=1$ supersymmetry in the context of Quantum Gravity Conjectures. According to the Emergent String Conjecture, infinite distance limits in quantum gravity either lead to decompactification of the theory or result in a weakly coupled string theory. We verify this conjecture in the framework of $N=1$ supersymmetric F-theory compactifications to four dimensions including perturbative $α'$ as well as non-perturbative corrections. After proving uniqueness of the emergent critical string at the classical level, we show that quantum corrections obstruct precisely those limits in which the scale of the emergent critical string would lie parametrically below the Kaluza-Klein scale. Limits in which the tension of the asymptotically tensionless string sits at the Kaluza-Klein scale, by contrast, are not obstructed. In the second part of the paper we study the effect of quantum corrections for the Weak Gravity Conjecture away from the strict weak coupling limit. We propose that gauge threshold corrections and mass renormalisation effects modify the super-extremality bound in four dimensions. For the infinite distance limits in F-theory the classical super-extremality bound is generically satisfied by a sublattice of states in the tower of excitations of an emergent heterotic string. By matching the F-theory $α'$ corrections to gauge threshold corrections of the dual heterotic theory we predict how the masses of this tower must be renormalised in order for the Weak Gravity Conjecture to hold at the quantum level.
description: 75 pages, 7 figures; v2: references added, typos corrected, minor clarifications; v3: references added, version accepted for publication in JHEP
The Generic Sudden Singularity in Brans-Dicke Theory
Creators: name: Barrow, John D.
name: Cotsakis, Spiros
name: Trachilis, Dimitrios
Publisher: name: arXiv
Year: 2020
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We construct a formal asymptotic series expansion for a general solution of the Brans-Dicke equations with a fluid source near a sudden singularity. This solution contains eleven independent arbitrary functions of the spatial coordinates as required by the Cauchy problem of the theory. We show that the solution is geodesically complete and has the character of a shock wave in the sudden asymptotic region. This solution is weak in the senses of Tipler and Krolak as in the corresponding case of general relativity.
description: 29 pages, to appear in the EPJC
Gravitational Quantum Foam and Supersymmetric Gauge Theories
Creators: name: Maeda, Takashi
name: Nakatsu, Toshio
name: Noma, Yui
name: Tamakoshi, Takeshi
Publisher: name: arXiv
Year: 2005
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: We study Kähler gravity on local SU(N) geometry and describe precise correspondence with certain supersymmetric gauge theories and random plane partitions. The local geometry is discretized, via the geometric quantization, to a foam of an infinite number of gravitational quanta. We count these quanta in a relative manner by measuring a deviation of the local geometry from a singular Calabi-Yau threefold, that is a A_{N-1} singularity fibred over \mathbb{P}^1. With such a regularization prescription, the number of the gravitational quanta becomes finite and turns to be the perturbative prepotential for five-dimensional \mathcal{N}=1 supersymmetric SU(N) Yang-Mills. These quanta are labelled by lattice points in a certain convex polyhedron on \mathbb{R}^3. The polyhedron becomes obtainable from a plane partition which is the ground state of a statistical model of random plane partition that describes the exact partition function for the gauge theory. Each gravitational quantum of the local geometry is shown to consist of N unit cubes of plane partitions.
description: 43 pages, 12 figures: V2 typos corrected
The Role of Text in Visualizations: How Annotations Shape Perceptions of Bias and Influence Predictions
Creators: name: Stokes, Chase
name: Bearfield, Cindy Xiong
name: Hearst, Marti A.
Publisher: name: arXiv
Year: 2024
Subjects: subject: Human-Computer Interaction (cs.HC)
subject: FOS: Computer and information sciences
subject: H.5.0

description: This paper investigates the role of text in visualizations, specifically the impact of text position, semantic content, and biased wording. Two empirical studies were conducted based on two tasks (predicting data trends and appraising bias) using two visualization types (bar and line charts). While the addition of text had a minimal effect on how people perceive data trends, there was a significant impact on how biased they perceive the authors to be. This finding revealed a relationship between the degree of bias in textual information and the perception of the authors' bias. Exploratory analyses support an interaction between a person's prediction and the degree of bias they perceived. This paper also develops a crowdsourced method for creating chart annotations that range from neutral to highly biased. This research highlights the need for designers to mitigate potential polarization of readers' opinions based on how authors' ideas are expressed.
description: 12 pages, 7 figures, for supplemental materials: https://github.com/chasejstokes/role-text
Single-top-quark production in the $t$-channel at NNLO
Creators: name: Campbell, John
name: Neumann, Tobias
name: Sullivan, Zack
Publisher: name: arXiv
Year: 2020
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: We present a calculation of t-channel single-top-quark production and decay in the five-flavor scheme at NNLO. Our results resolve a disagreement between two previous calculations of this process that found a difference in the inclusive cross section at the level of the NNLO coefficient itself. We compare in detail with the previous calculations at the inclusive, differential and fiducial level including b-quark tagging at a fixed scale $μ=m_t$. In addition, we advocate the use of double deep inelastic scattering (DDIS) scales ($μ^2=Q^2$ for the light-quark line and $μ^2=Q^2+m_t^2$ for the heavy-quark line) that maximize perturbative stability and allow for robust scale uncertainties. All NNLO and NLO$\,\otimes\,$NLO contributions for production and decay are included in the on-shell and vertex-function approximation. We present fiducial and differential results for a variety of observables used in Standard Model and Beyond Standard Model analyses, and find an important difference between the NLO and NNLO predictions of exclusive $t+n$-jet cross sections. Overall we find that NNLO corrections are crucial for a precise identification of the t-channel process.
description: 40 pages, 22 figures, JHEP published version
Singlet structure function g_1 at small x and small Q^2
Creators: name: Ermolaev, B. I.
name: Greco, M.
name: Troyan, S. I.
Publisher: name: arXiv
Year: 2006
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: Explicit expressions for the singlet g_1 at small x and small Q^2 are obtained with the total resummation of the leading logarithmic contributions. It is shown that g_1 practically does not depend on Q^2 in this kinematic region. In contrast, it would be interesting to investigate its dependence on the invariant energy 2pq because, being g_1 positive at small 2pq, it can turn negative at greater values of this variable. The position of the turning point is sensitive to the ratio between the initial quark and gluon densities, so its experimental detection would enable to estimate this ratio
description: Section 2 is totally changed, one more ref added
Two-level Nyström--Schur preconditioner for sparse symmetric positive definite matrices
Creators: name: Daas, Hussam Al
name: Rees, Tyrone
name: Scott, Jennifer
Publisher: name: arXiv
Year: 2021
Subjects: subject: Numerical Analysis (math.NA)
subject: FOS: Mathematics

description: Randomized methods are becoming increasingly popular in numerical linear algebra. However, few attempts have been made to use them in developing preconditioners. Our interest lies in solving large-scale sparse symmetric positive definite linear systems of equations where the system matrix is preordered to doubly bordered block diagonal form (for example, using a nested dissection ordering). We investigate the use of randomized methods to construct high quality preconditioners. In particular, we propose a new and efficient approach that employs Nyström's method for computing low rank approximations to develop robust algebraic two-level preconditioners. Construction of the new preconditioners involves iteratively solving a smaller but denser symmetric positive definite Schur complement system with multiple right-hand sides. Numerical experiments on problems coming from a range of application areas demonstrate that this inner system can be solved cheaply using block conjugate gradients and that using a large convergence tolerance to limit the cost does not adversely affect the quality of the resulting Nyström--Schur two-level preconditioner.
Gerl, Hanna-Barbara: Romano Guardini 1885-1968
Creators: name: Krüger, Hanfried
Publisher: name: Ökumenische Rundschau
Year: 2025

description: Ökumenische Rundschau, Bd. 34 Nr. 2 (1985): Ökumenische Rundschau, Band 34, Heft 2
The freckling mechanism of superalloys
Creators: name: Wang, Tao
Publisher: name: University of British Columbia
Year: 2009

description: Freckles are macro-segregation defects which are usually found in nickel-base superalloys or specialty steels and which occur during solidification. They are presently one of the major defects encountered in advanced casting technology of superalloys. Two modified Rayleigh criteria have been suggested which seem best adapted to freckling prediction. However only three superalloys have been previously tested for the application of the modified Rayleigh numbers and fAirther experiments on industrial alloys and in casting conditions similar to actual industry conditions are therefore needed. There are* conflicting reports as to the cause of freckling in IN718 alloy. One possible explanation is that freckling is caused by a downward interdendritic flow along the slope of solidification front, another possible explanation is that freckle may be caused by the density inversion between the interdendritic liquid and bulk liquid in the same way as in other superalloys. The Si content is believed play a critical role in influencing the freckle formation in IN718, without however any confirming experiment data. A vacuum induction furnace was built so as to directionally solidify superalloys at various angles to the vertical under typical industrial conditions (thermal gradients ranging from 500 to 4000°C/m (5 to 40°C/cm) and growth rates ranging from 1.6 x 10"5 to 10 x 10"5 m/s (1 to 6 mm/min). A comprehensive thermal modeling of this furnace was carried out with the FEM package ProCAST in order to accurately evaluate the solidification conditions (G and R) for each casting. Totally 10 alloys were tested and the modified Rayleigh criteria are shown to be able to predict freckling in all these alloys under different casting conditions and different growth front angles. Si content is shown to influence the density of the interdendritic liquid and hence the freckling mechanism in IN718.
Spectral functions from the Functional Renormalization Group
Creators: name: Tripolt, R.
name: Von Smekal, L.
name: Wambach, J.
Publisher: name: GSI Helmholtzzentrum fuer Schwerionenforschung, Darmstadt
Year: 2015
Subjects: Physics

description: GSI Scientific Report 2014 - GSI Report 2015-1
The O(4) criticality in the net-baryon number probability distribution
Creators: name: Morita, K.
name: Friman, B.
name: Redlich, Krzysztof
Publisher: name: GSI Helmholtzzentrum fuer Schwerionenforschung, Darmstadt
Year: 2015
Subjects: Physics

description: GSI Scientific Report 2014 - GSI Report 2015-1
Fluctuations of the Polyakov loop in the heavy quark regime
Creators: name: Lo, P. M.
name: Friman, B.
name: Redlich, Krzysztof
Publisher: name: GSI Helmholtzzentrum fuer Schwerionenforschung, Darmstadt
Year: 2015
Subjects: Physics

description: GSI Scientific Report 2014 - GSI Report 2015-1
A novel Monte-Carlo approach to particle-field dynamics
Creators: name: Wesp, C.
name: Van Hees, H.
name: Meistrenko, A.
name: Greiner, Carsten
Publisher: name: GSI Helmholtzzentrum fuer Schwerionenforschung, Darmstadt
Year: 2015
Subjects: Physics

description: GSI Scientific Report 2014 - GSI Report 2015-1
Systematic investigation of Cooper-Frye negative contributions
Creators: name: Oliinychenko, D.
name: Huovinen, P.
name: Petersen, H.
Publisher: name: GSI Helmholtzzentrum fuer Schwerionenforschung, Darmstadt
Year: 2015
Subjects: Physics

description: GSI Scientific Report 2014 - GSI Report 2015-1
Strange meson-baryon interaction in hot and dense nuclear matter: from hadronic models to transport simulations
Creators: name: Cabrera, D.
name: Ilner, A.
name: Tolos, L.
name: Aichelin, J.
name: Bratkovskaya, E.
name: Cassing, W.
Publisher: name: GSI Helmholtzzentrum fuer Schwerionenforschung, Darmstadt
Year: 2015
Subjects: Physics

description: GSI Scientific Report 2014 - GSI Report 2015-1
Formation of hypermatter and hypernuclei within transport models in relativistic ion collisions
Creators: name: Botvina, A.
name: Steinheimer, J.
name: Bratkovskaya, E.
name: Bleicher, M.
name: Pochodzalla, J.
Publisher: name: GSI Helmholtzzentrum fuer Schwerionenforschung, Darmstadt
Year: 2015
Subjects: Physics

description: GSI Scientific Report 2014 - GSI Report 2015-1
The Struggles of Feature-Based Explanations: Shapley Values vs. Minimal Sufficient Subsets
Creators: name: Camburu, Oana-Maria
name: Giunchiglia, Eleonora
name: Foerster, Jakob
name: Lukasiewicz, Thomas
name: Blunsom, Phil
Publisher: name: arXiv
Year: 2020
Subjects: subject: Computation and Language (cs.CL)
subject: FOS: Computer and information sciences

description: For neural models to garner widespread public trust and ensure fairness, we must have human-intelligible explanations for their predictions. Recently, an increasing number of works focus on explaining the predictions of neural models in terms of the relevance of the input features. In this work, we show that feature-based explanations pose problems even for explaining trivial models. We show that, in certain cases, there exist at least two ground-truth feature-based explanations, and that, sometimes, neither of them is enough to provide a complete view of the decision-making process of the model. Moreover, we show that two popular classes of explainers, Shapley explainers and minimal sufficient subsets explainers, target fundamentally different types of ground-truth explanations, despite the apparently implicit assumption that explainers should look for one specific feature-based explanation. These findings bring an additional dimension to consider in both developing and choosing explainers.
Coherent wave control in complex media with arbitrary wavefronts
Creators: name: del Hougne, Philipp
name: Yeo, K. Brahima
name: Besnier, Philippe
name: Davy, Matthieu
Publisher: name: arXiv
Year: 2020
Subjects: subject: Applied Physics (physics.app-ph)
subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: Wavefront shaping (WFS) has emerged as powerful tool to control the propagation of diverse wave phenomena (light, sound, microwaves, ...) in disordered matter for applications including imaging, communication, energy transfer, micromanipulation, and scattering anomalies. Nonetheless, in practice the necessary coherent control of multiple input channels remains a vexing problem. Here, we overcome this difficulty by doping the disordered medium with programmable meta-atoms in order to adapt it to an imposed arbitrary incoming wavefront. Besides lifting the need for carefully shaped incident wavefronts, our approach also unlocks new opportunities such as sequentially achieving different functionalities with the same arbitrary wavefront. We demonstrate our concept experimentally for electromagnetic waves using programmable metasurfaces in a chaotic cavity, with applications to focusing with the generalized Wigner-Smith operator as well as coherent perfect absorption. We expect our fundamentally new perspective on coherent wave control to facilitate the transition of intricate WFS protocols into real applications for various wave phenomena.
description: 13 pages including 4 figures + 7 pages Supplemental Material
Multi-layer atom chips for versatile atom micro manipulation
Creators: name: Trinker, Martin
name: Groth, Sönke
name: Haslinger, Stefan
name: Manz, Stephanie
name: Betz, Thomas
name: Bar-Joseph, Israel
name: Schumm, Thorsten
name: Schmiedmayer, Jörg
Publisher: name: arXiv
Year: 2008
Subjects: subject: Atomic Physics (physics.atom-ph)
subject: Instrumentation and Detectors (physics.ins-det)
subject: FOS: Physical sciences

description: We employ a combination of optical UV- and electron-beam-lithography to create an atom chip combining sub-micron wire structures with larger conventional wires on a single substrate. The new multi-layer fabrication enables crossed wire configurations, greatly enhancing the flexibility in designing potentials for ultra cold quantum gases and Bose-Einstein condensates. Large current densities of >6 x 10^7 A/cm^2 and high voltages of up to 65 V across 0.3 micron gaps are supported by even the smallest wire structures. We experimentally demonstrate the flexibility of the next generation atom chip by producing Bose-Einstein condensates in magnetic traps created by a combination of wires involving all different fabrication methods and structure sizes.
description: 4 pages, 5 figures
A Field and Laboratory Compaction Study of a Mixture of Retorted and Raw Oil Shale from the Means Project in Montgomery County
Creators: name: Allen, David L.
name: Meade, Bobby W.
Publisher: name: Kentucky Transportation Center, University of Kentucky
Year: 1984
Subjects: subject: Transportation Engineering

description: The oil shale retorting process will produce large volumes of spent shale and some raw oil shale that cannot he used in the retorting process. Consequently, it is anticipated that on-site disposal embankments will be constructed using these materials A report by Drnevich, et al. (1) has recommended that site-specific compaction studies be done at the start up of a mining and disposal operation. Holtz 12) has reported on a detailed study of the compaction characteristics of a western oil shale that had been retorted by the Paraho vertical retort process.  This study was performed to develop background data on compaction characteristics of retorted material when mixed with a small percentage of raw shale that is generated as a result of the crushing process. The test site was located in Montgomery County, Kentucky, and the shales that were used were the Sunbury and Cleveland oil shales obtained in the same county.
A Review and Analysis of Pile Design
Creators: name: Allen, David L.
Publisher: name: Kentucky Transportation Center, University of Kentucky
Year: 1984
Subjects: subject: Transportation Engineering

description: A review of lateral load design of piles is presented. It appears many different methods and allowable lateral loads are permitted by the states. One particular method is discussed in detail, and from that method two charts are presented that relate pile deflection to lateral load. Recommendations are given on design criteria for lateral loads.  A review of allowable axial stresses is also presented. The results of a brief finite element analysis of pile tip settlement versus load for various conditions are also presented. These results are compared to data obtained from the literature. Recommendations on maximum allowable axial stress are given.
Observation of Spin Susceptibility Enhancement in the Possible FFLO State in CeCoIn$_5$
Creators: name: Mitrovic, V. F.
name: Horvatic, M.
name: Berthier, C.
name: Knebel, G.
name: Lapertot, G.
name: Flouquet, J.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: We report $^{115}$In nuclear magnetic resonance (NMR) measurements of the heavy-fermion superconductor CeCoIn$_5$ in the vicinity of the superconducting critical field $H_{c2}$ for a magnetic field applied perpendicular to the $\hat c$-axis. A possible inhomogeneous superconducting state, Fulde-Ferrel-Larkin-Ovchinnikov (FFLO), is stabilized in this part of the phase diagram. In 11 T applied magnetic field, we observe clear signatures of the two phase transitions: the higher temperature one to the homogeneous superconducting state and the lower temperature phase transition to a FFLO state. It is found that the spin susceptibility in the putative FFLO state is significantly enhanced as compared to the value in a homogeneous superconducting state. Implications of this finding for the nature of the low temperature phase are discussed.
description: to appear in Phys. Rev. Lett
Fast, cheap, and scalable magnetic tracker with an array of magnetoresistors
Creators: name: Biancalana, Valerio
name: Cecchi, Roberto
name: Chessa, Piero
name: Bevilacqua, Giuseppe
name: Dancheva, Yordanka
name: Vigilante, Antonio
Publisher: name: arXiv
Year: 2020
Subjects: subject: Instrumentation and Detectors (physics.ins-det)
subject: FOS: Physical sciences

description: We present the hardware of a cheap multi-sensor magnetometric setup where a relatively large set of magnetic field components is measured in several positions by calibrated magnetoresistive detectors. The setup is developed with the scope of mapping the (inhomogeneous) field generated by a known magnetic source, which is measured as superimposed to the (homogeneous) geomagnetic field. The final goal is to use the data produced by this hardware to reconstruct position and orientation of the magnetic source with respect to the sensor frame, simultaneously with the orientation of the frame with respect to the environmental field. Possible applications of the setup are shortly discussed, together with a synthetic description of the data elaboration and analysis.
description: 10 pages, 7 figures, 30 refs
อิทธิพลของวิธีการสกัดต่อผลได้การสกัดและฤทธิ์การต้านอนุมูลอิสระของสารสกัดพืชสมุนไพรไทย
Creators: name: ศรัณยู อุ่นทวี
Publisher: name: Thammasat University
Year: 2019
Subjects: extraction method
extraction yield
antioxidant activity
herbal plant
chrysanthemum flower

description: Thai Journal of Science and Technology, 8, 5, 493-508
The Effect of Spiral Structure on the Stellar Velocity Distribution in the Solar Neighborhood
Creators: name: Quillen, A. C.
name: Minchev, Ivan
Publisher: name: arXiv
Year: 2005
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: Clumps in the solar neighborhood's stellar velocity distribution could be caused by spiral density waves. In the solar neighborhood, stellar velocities corresponding to orbits that are nearly closed in the frame rotating with a spiral pattern represent likely regions for stellar concentrations. Via particle integration, we show that orbits can intersect the solar neighborhood when they are excited by Lindblad resonances with a spiral pattern. We find that a two-armed spiral density wave with pattern speed placing the Sun near the 4:1 Inner Lindblad Resonance (ILR) can cause two families of nearly closed orbits in the solar neighborhood. One family corresponds to square shaped orbits aligned so their peaks lie on top of, and support, the two dominant stellar arms. The second family correspond to orbits 45 degrees out of phase with the other family. Such a spiral density pattern could account for two major clumps in the solar neighborhood's velocity distribution. The Pleiades/Hyades moving group corresponds to the first family of orbits and the Coma Berenices moving group corresponds to the second family. This model requires a spiral pattern speed of approximately 0.66 +- 0.03 times the angular rotation rate of the Sun or 18.1 +- 0.8 km/s/kpc.
description: Accepted for publication in AJ
A Generalized It$\hat {\rm o}$'s Formula in Two-Dimensions and Stochastic Lebesgue-Stieltjes Integrals
Creators: name: Feng, Chunrong
name: Zhao, Huaizhong
Publisher: name: arXiv
Year: 2005
Subjects: subject: Probability (math.PR)
subject: FOS: Mathematics
subject: 60H05, 60J55

description: A generalized It${\hat {\rm o}}$ formula for time dependent functions of two-dimensional continuous semi-martingales is proved. The formula uses the local time of each coordinate process of the semi-martingale, left space and time first derivatives and second derivative $\nabla_1^- \nabla_2^-f$ only which are assumed to be of locally bounded variation in certain variables, and stochastic Lebesgue-Stieltjes integrals of two parameters.The two-parameter integral is defined as a natural generalization of the It${\hat {\rm o}}$ integral and Lebesgue-Stieltjes integral through a type of It${\hat {\rm o}}$ isometry formula.
description: Modify pages 4-9 and add more references
Inclusive and exclusive neutrino-nucleus cross sections and the reconstruction of the interaction kinematics
Creators: name: Bourguille, Bruno
name: Nieves, Juan
name: Sanchez, Federico
Publisher: name: arXiv
Year: 2020
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: We present a full kinematic analysis of neutrino-nucleus charged current quasielastic interactions based on the Local Fermi Gas model and the Random PhaseApproximation. The model was implemented in the NEUT Monte Carlo framework, which allows us to investigate potentially measurable observables, including hadron distributions. We compare the predictions simultaneously to the most recent T2K and MINERvA charged current (CC) inclusive, CC0$π$ and transverse kinematic-imbalance variable results. We pursuit a microscopic interpretation of the relevant reaction mechanisms, with the aim of achieving in neutrino oscillation experiments a correct reconstruction of the incoming neutrino kinematics, free of conceptual biasses. Such study is of the utmost importance for the ambitious experimental program which is underway to precisely determine neutrino properties, test the three-generation paradigm, establish the order of mass eigenstates and investigate leptonic CP violation.
Bayesian inversion for electromyography using low-rank tensor formats
Creators: name: Rörich, Anna
name: Werthmann, Tim A.
name: Göddeke, Dominik
name: Grasedyck, Lars
Publisher: name: arXiv
Year: 2020
Subjects: subject: Numerical Analysis (math.NA)
subject: FOS: Mathematics

description: The reconstruction of the structure of biological tissue using electromyographic data is a non-invasive imaging method with diverse medical applications. Mathematically, this process is an inverse problem. Furthermore, electromyographic data are highly sensitive to changes in the electrical conductivity that describes the structure of the tissue. Modeling the inevitable measurement error as a stochastic quantity leads to a Bayesian approach. Solving the discretized Bayes-inverse problem means drawing samples from the posterior distribution of parameters, e.g., the conductivity, given measurement data. Using, e.g., a Metropolis-Hastings algorithm for this purpose involves solving the forward problem for different parameter combinations which requires a high computational effort. Low-rank tensor formats can reduce this effort by providing a data-sparse representation of all occurring linear systems of equations simultaneously and allow for their efficient solution. The application of Bayes' theorem proves the well-posedness of the Bayes-inverse problem. The derivation and proof of a low-rank representation of the forward problem allow for the precomputation of all solutions of this problem under certain assumptions, resulting in an efficient and theory-based sampling algorithm. Numerical experiments support the theoretical results, but also indicate that a high number of samples is needed to obtain reliable estimates for the parameters. The Metropolis-Hastings sampling algorithm, using the precomputed forward solution in a tensor format, draws this high number of samples and therefore enables solving problems which are infeasible using classical methods.
Quantum critical behavior in itinerant electron systems -- Eliashberg theory and instability of a ferromagnetic quantum-critical point
Creators: name: Rech, J.
name: Pepin, C.
name: Chubukov, A. V.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We consider the problem of fermions interacting with gapless long-wavelength collective bosonic modes. The theory describes, among other cases, a ferromagnetic quantum-critical point (QCP) and a QCP towards nematic ordering. We construct a controllable expansion at the QCP in two steps: we first create a new, non Fermi-liquid ``zero-order'' Eliashberg-type theory, and then demonstrate that the residual interaction effects are small. We prove that this approach is justified under two conditions: the interaction should be smaller than the fermionic bandwidth, and either the band mass $m_B$ should be much smaller than $m = p_F/v_F$, or the number of fermionic flavors $N$ should be large. For an SU(2) symmetric ferromagnetic QCP, we find that the Eliashberg theory itself includes a set of singular renormalizations which can be understood as a consequence of an effective long-range dynamic interaction between quasi-particles, generated by the Landau damping term. These singular renormalizations give rise to a negative non-analytic $q^{3/2}$ correction to the static spin susceptibility, and destroy a ferromagnetic QCP. We demonstrate that this effect can be understood in the framework of the $ϕ^4$ theory of quantum criticality. We also show that the non-analytic $q^{3/2}$ correction to the bosonic propagator is specific to the SU(2) symmetric case. For systems with a scalar order parameter, the $q^{3/2}$ contributions from individual diagrams cancel out in the full expression of the susceptibility, and the QCP remains stable.
description: 37 pages, 10 figs
Solitons of Bose-Fermi mixtures in a strongly elongated trap
Creators: name: Santhanam, J.
name: Kenkre, V. M.
name: Konotop, V. V.
Publisher: name: arXiv
Year: 2005
Subjects: subject: Other Condensed Matter (cond-mat.other)
subject: FOS: Physical sciences

description: It is shown that a Bose-Fermi mixture of a degenerate gas of spin-polarized fermions, whose number significantly exceeds the number of bosons, embedded in a strongly anisotropic trap, is described by the one-dimensional coupled nonlinear Schrodinger equation for the boson component and the wave equation with external source for the fermion component. Depending on the type of boson-fermion interaction, the system may display modulational instability and the existence of solitons in the fermion and boson components respectively. Such solitons represent either a local decrease (increase) of the density of both the components or a decrease of the density in one component and an increase of the density in the other component. It is shown that the type of the effective interactions can be easily managed by varying the trap geometry or by means of Feshbach resonance.
description: 1 figure
Effective-Lagrangian approach to gamma gamma --> WW; II: Results and comparison with e+e- --> WW
Creators: name: Nachtmann, O.
name: Nagel, F.
name: Pospischil, M.
name: Utermann, A.
Publisher: name: arXiv
Year: 2005
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We present a study of anomalous electroweak gauge-boson couplings which can be measured in e+e- and gamma gamma collisions at a future linear collider like ILC. We consider the gauge-boson sector of a locally SU(2) x U(1) invariant effective Lagrangian with ten dimension-six operators added to the Lagrangian of the Standard Model. These operators induce anomalous three- and four-gauge-boson couplings and an anomalous gamma gamma H coupling. We calculate the reachable sensitivity for the measurement of the anomalous couplings in gamma gamma --> WW. We compare these results with the reachable precision in the reaction e+e- --> WW on the one hand and with the bounds that one can get from high-precision observables in Z decays on the other hand. We show that one needs both the e+e- and the gamma gamma modes at an ILC to constrain the largest possible number of anomalous couplings and that the Giga-Z mode offers the best sensitivity for certain anomalous couplings.
description: 25 pages, 1 figure, 7 tables, comments, references and a table added; to appear in EPJC
Two-Color Fabry-Perot Laser Diode with THz Primary Mode Spacing
Creators: name: O'Brien, S.
name: Osborne, S.
name: Buckley, K.
name: Fehse, R.
name: Amann, A.
name: O'Reilly, E. P.
name: Barry, L. P.
name: Anandarajah, P.
name: Patchell, J.
name: O'Gorman, J.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: A class of multiwavelength Fabry-Perot lasers is introduced where the spectrum is tailored through a non-periodic patterning of the cavity effective index. The cavity geometry is obtained using an inverse scattering approach and can be designed such that the spacing of discrete Fabry-Perot lasing modes is limited only by the bandwidth of the inverted gain medium. A specific two-color semiconductor laser with a mode spacing in the THz regime is designed, and measurements are presented demonstrating the simultaneous oscillation of the two wavelengths. The extension of the Fabry-Perot laser concept described presents significant new possibilities in laser cavity design.
description: 5 pages, 4 figures
Parameterized Reinforcement Learning for Optical System Optimization
Creators: name: Wankerl, Heribert
name: Stern, Maike L.
name: Mahdavi, Ali
name: Eichler, Christoph
name: Lang, Elmar W.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Machine Learning (cs.LG)
subject: Artificial Intelligence (cs.AI)
subject: Optics (physics.optics)
subject: FOS: Computer and information sciences
subject: FOS: Physical sciences

description: Designing a multi-layer optical system with designated optical characteristics is an inverse design problem in which the resulting design is determined by several discrete and continuous parameters. In particular, we consider three design parameters to describe a multi-layer stack: Each layer's dielectric material and thickness as well as the total number of layers. Such a combination of both, discrete and continuous parameters is a challenging optimization problem that often requires a computationally expensive search for an optimal system design. Hence, most methods merely determine the optimal thicknesses of the system's layers. To incorporate layer material and the total number of layers as well, we propose a method that considers the stacking of consecutive layers as parameterized actions in a Markov decision process. We propose an exponentially transformed reward signal that eases policy optimization and adapt a recent variant of Q-learning for inverse design optimization. We demonstrate that our method outperforms human experts and a naive reinforcement learning algorithm concerning the achieved optical characteristics. Moreover, the learned Q-values contain information about the optical properties of multi-layer optical systems, thereby allowing physical interpretation or what-if analysis.
description: Presented as a poster at the workshop on machine learning for engineering modeling, simulation and design @ NeurIPS 2020
A study of DVB-T2 standard with physical layer transceiver design and implementation
Creators: name: Yu, Mingchao
Publisher: name: The Australian National University
Year: 2011
Subjects: subject: TK6678.5.D87 Y8 2011
subject: Digital television Standards
subject: Television broadcasting.

description: The second generation of terrestrial digital video broadcasting (DVB-T2) standard was published by European Telecommunications Standards Institute in 2008. Compared with the previous DVB-T, the new standard offers better robustness to severe channel conditions and provides up to 60% data capacity increment. These performance improvements are achieved through the adoption of new channel coding and modulation techniques. This thesis concentrates on the physical layer transceiver of DVB-T2, including bit-interleaved coded modulation (BICM) module, frame mapper module, and orthogonal-frequency-division-multiplexing (OFDM) modulation module. We established a baseband physical layer DVB-T2 system model and thoroughly studied new techniques included in the transmitter and their receiving methods, including Bose-Chaudhuri-Hocquenghemand (BCH) codes, low-density parity{u00AD}check (LDPC) codes, iterative BICM with rotated constellation, P1 preamble OFDM symbol, and two OFDM peak-to-average power ratio (PAPR) reduction techniques. We then proposed some techniques for transceiver optimization. The main outcomes are: 1. an efficient BCH encoding/decoding algorithm; 2. a low-complexity iterative demapping and decoding algorithm; 3. novel time domain synchronization and decoding methods for P1 OFDM symbol; 4. a novel low-complexity time domain channel estimation method for normal OFDM symbol. Each transceiver module was first implemented and had their performance evaluated separately. Then they were assembled to investigate the end-to-end bit-error-rate (BER) performance of the complete baseband physical layer DVB-T2 transceiver. Simulated channel types are additive white Gaussian noise (AWGN) channel, multipath Ricean fading channel, multipath Rayleigh fading channel and multipath mobile channel. The correctness of our system was confirmed by comparing the simulation results with the performance reported in the official implementation guidelines published by digital video broadcasting (DVB) group.
Creation and annihilation of antimatter at FAIR energies
Creators: name: Moreau, P.
name: Aichelin, J.
name: Bratkovskaya, E.
Publisher: name: GSI Helmholtzzentrum fuer Schwerionenforschung, Darmstadt
Year: 2015
Subjects: Physics

description: GSI Scientific Report 2014 - GSI Report 2015-1
On demand single photon source using a nanoscale metal-insulator-semiconductor capacitor
Creators: name: Hu, Binhui
name: Yang, C. H.
name: Yang, M. J.
Publisher: name: arXiv
Year: 2005
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We propose an on-demand single photon source for quantum cryptography using a metal-insulator-semiconductor quantum dot capacitor structure. The main component in the semiconductor is a p-doped quantum well, and the cylindrical gate under consideration is only nanometers in diameter. As in conventional metal-insulator-semiconductor capacitors, our system can also be biased into the inversion regime. However, due to the small gate area, at the onset of inversion there are only a few electrons residing in a quantum dot. In addition, because of the strong size quantization and large Coulomb energy, the number of electrons can be precisely controlled by the gate voltage. After holding just one electron in the inversion layer, the capacitor is quickly biased back to the flat band condition, and the subsequent radiative recombination across the bandgap results in single photon emission. We present numerical simulation results of a semiconductor heterojunction and discuss the merits of this single photon source.
description: 15 pages, including 3 figures
Charm production in the Parton-Hadron-String-Dynamics (PHSD) model
Creators: name: Song, T.
name: Bratkovskaya, E.
name: Berrehrah, H.
name: Cassing, W.
Publisher: name: GSI Helmholtzzentrum fuer Schwerionenforschung, Darmstadt
Year: 2015
Subjects: Physics

description: GSI Scientific Report 2014 - GSI Report 2015-1
Helicity, Spin, and Infra-zilch of Light: a Lorentz Covariant Formulation
Creators: name: Aghapour, Sajad
name: Andersson, Lars
name: Rosquist, Kjell
Publisher: name: arXiv
Year: 2020
Subjects: subject: Optics (physics.optics)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: In this paper, a novel conserved Lorentz covariant tensor, termed the helicity tensor, is introduced in Maxwell theory. The conservation of the helicity tensor expresses the conservation laws contained in the helicity array, introduced by Cameron et al., including helicity, spin, and the spin-flux or infra-zilch. The Lorentz covariance of the helicity tensor is in contrast to previous formulations of the helicity hierarchy of conservation laws, which required the non-Lorentz covariant transverse gauge. The helicity tensor is shown to arise as a Noether current for a variational symmetry of a duality-symmetric Lagrangian for Maxwell theory. This symmetry transformation generalizes the duality symmetry and includes the symmetry underlying the conservation of the spin part of the angular momentum.
description: 13 pages, 1 table, no figures
Heavy-quark dynamics in a hot and dense medium
Creators: name: Berrehrah, H.
name: Bratkovskaya, E.
name: Cassing, W.
name: Gossiaux, P.
name: Aichelin, J.
Publisher: name: GSI Helmholtzzentrum fuer Schwerionenforschung, Darmstadt
Year: 2015
Subjects: Physics

description: GSI Scientific Report 2014 - GSI Report 2015-1
Analytic solution to N vs. M photon phase control in an open two-level system
Creators: name: Han, Heekyung
name: Brumer, Paul
Publisher: name: arXiv
Year: 2005
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Decoherence effects on the traditional N vs. M photon coherent control of a two-level system are investigated, with 1 vs. 3 used as a specific example. The problem reduces to that of a two-level system interacting with a single mode field, but with an effective Rabi frequency that depends upon the fundamental and third harmonic fields. The resultant analytic control solution is explored for a variety of parameters, with emphasis on the dependence of control on the relative phase of the lasers. The generalization to off-resonant cases is noted.
description: 15 pages, 2 figures, to be published in Chem. Phys. Lett
Screening studies with Microsoft Excel for systematic reviews and meta-analysis
Creators: name: M.J. Lajeunesse
Publisher: name: figshare
Year: 2021
Subjects: subject: 10401 Applied Statistics
subject: FOS: Mathematics

description: A common task in research synthesis projects, like meta-analysis or systematic reviews, is the screening of individual studies for inclusion.

In this YouTube video, a quick tutorial is presented to show how to create a simple interface to facilitate the screening process.
YOUTUBE VIDEO: https://youtu.be/7KbKuZm6JFk
What is all this new MeSH about? Exploring the semantic provenance of new descriptors in the MeSH thesaurus
Creators: name: Nentidis, Anastasios
name: Krithara, Anastasia
name: Tsoumakas, Grigorios
name: Paliouras, Georgios
Publisher: name: arXiv
Year: 2021
Subjects: subject: Digital Libraries (cs.DL)
subject: Information Retrieval (cs.IR)
subject: FOS: Computer and information sciences

description: The Medical Subject Headings (MeSH) thesaurus is a controlled vocabulary widely used in biomedical knowledge systems, particularly for semantic indexing of scientific literature. As the MeSH hierarchy evolves through annual version updates, some new descriptors are introduced that were not previously available. This paper explores the conceptual provenance of these new descriptors. In particular, we investigate whether such new descriptors have been previously covered by older descriptors and what is their current relation to them. To this end, we propose a framework to categorize new descriptors based on their current relation to older descriptors. Based on the proposed classification scheme, we quantify, analyse and present the different types of new descriptors introduced in MeSH during the last fifteen years. The results show that only about 25% of new MeSH descriptors correspond to new emerging concepts, whereas the rest were previously covered by one or more existing descriptors, either implicitly or explicitly. Most of them were covered by a single existing descriptor and they usually end up as descendants of it in the current hierarchy, gradually leading towards a more fine-grained MeSH vocabulary. These insights about the dynamics of the thesaurus are useful for the retrospective study of scientific articles annotated with MeSH, but could also be used to inform the policy of updating the thesaurus in the future.
description: 18 pages, 14 figures, 2 tables
Iron, ruthenium and osmium alkynyl complexes : syntheses, linear optical and computational studies
Creators: name: Abdul Razak, Fazira Ilyana
Publisher: name: The Australian National University
Year: 2015

description: Metal alkynyl complexes are of interest for a variety of possible applications, one being their use as advanced nonlinear optical (NLO) materials. This Thesis describes the synthesis and characterization, along with computational studies, of group 8 metal alkynyl complexes, which may exhibit interesting NLO properties. Chapter 1 discusses the theoretical background of NLO properties. This is followed by a brief review of the research that has been conducted in the field of organometallic NLO materials. Chapter 2 focuses on the syntheses of group 8 metal acetylide complexes possessing dipolar and octupolar configurations. Syntheses of both linear and branched substitution on the aryl core of either homo- or heterometallic complexes are described here, as well as crystal structures. The physical properties of these complexes are examined using a range of measurements, including cyclic voltammetry, IR and UV-vis spectroscopy. Chapter 3 covers the computational studies of the synthesized and unsynthesized complexes in Chapter 2 using the time-dependent density functional theory (TD-DFT) method. The computed linear and nonlinear optical data allow for a better understanding of the molecular electronic structure responsible for the experimental data.
Quantum annealing of Cayley-tree Ising spins at small scales
Creators: name: Song, Yunheung
name: Kim, Minhyuk
name: Hwang, Hansub
name: Lee, Woojun
name: Ahn, Jaewook
Publisher: name: arXiv
Year: 2020
Subjects: subject: Quantum Physics (quant-ph)
subject: Atomic Physics (physics.atom-ph)
subject: FOS: Physical sciences

description: Significant efforts are being directed towards developing a quantum annealer capable of solving combinatorial optimization problems. The challenges are Hamiltonian programming and large-scale implementations. Here we report quantum annealing demonstration of Ising Hamiltonians programmed with up to $N=22$ spins mapped on various Cayley tree graphs. Experiments are performed with a Rydberg-atom quantum simulator, in which rubidium single atoms are arranged in three dimensional space in such a way that their Rydberg atoms and blockaded strong couplings respectively represent the nodes and edges of each graph. Three different Cayley-tree graphs of $Z=3$ neighbors and of up to $S=4$ shells are constructed, and their ground-state phases and Néel's order formations are probed. In good agreement with model calculations, the anti-ferromagnetic phase in regular Cayley trees and frustrated competing ground-states in a dual-center Cayley tree are directly observed. This demonstrates the possibilities of high-dimensional qubit connection programming in quantum simulators.
description: 7 pages,5 figures