cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Black holes within Asymptotic Safety
Creators: name: Koch, Benjamin
name: Saueressig, Frank
Publisher: name: arXiv
Year: 2014
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: Black holes are probably among the most fascinating objects populating our universe. Their characteristic features found within general relativity, encompassing spacetime singularities, event horizons, and black hole thermodynamics, provide a rich testing ground for quantum gravity ideas. We review the status of black holes within a particular proposal for quantum gravity, Weinberg's asymptotic safety program. Starting from a brief survey of the effective average action and scale setting procedures, an improved quantum picture of the black hole is developed. The Schwarzschild black hole and its generalizations including angular momenta, higher-derivative corrections and the implications of extra dimensions are discussed in detail. In addition, the quantum singularity emerging for the inclusion of a cosmological constant is elucidated and linked to the phenomenon of a dynamical dimensional reduction of spacetime.
description: 42 pages; Invited review for International Journal of Modern Physics A
Measurements of the γ* p --> Δ(1232) reaction at low Q2
Creators: name: Sparveris, N.
name: Stave, S.
name: Achenbach, P.
name: Gayoso, C. Ayerbe
name: Baumann, D.
name: Bernauer, J.
name: Bernstein, A. M.
name: Bohm, R.
name: Bosnar, D.
name: Botto, T.
name: Christopoulou, A.
name: Dale, D.
name: Ding, M.
name: Distler, M. O.
name: Doria, L.
name: Friedrich, J.
name: Karabarbounis, A.
name: Makek, M.
name: Merkel, H.
name: Muller, U.
name: Nakagawa, I.
name: Neuhausen, R.
name: Nungesser, L.
name: Papanicolas, C. N.
name: Piegsa, A.
name: Pochodzalla, J.
name: Potokar, M.
name: Seimetz, M.
name: Sirca, S.
name: Stiliaris, S.
name: Walcher, Th.
name: Weis, M.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Nuclear Experiment (nucl-ex)
subject: FOS: Physical sciences

description: We report new p$(\vec{e},e^\prime p)π^\circ$ measurements in the $Δ^{+}(1232)$ resonance at the low momentum transfer region utilizing the magnetic spectrometers of the A1 Collaboration at MAMI. The mesonic cloud dynamics are predicted to be dominant and appreciably changing in this region while the momentum transfer is sufficiently low to be able to test chiral effective calculations. The results disagree with predictions of constituent quark models and are in reasonable agreement with dynamical calculations with pion cloud effects, chiral effective field theory and lattice calculations. The reported measurements suggest that improvement is required to the theoretical calculations and provide valuable input that will allow their refinements.
Estimating Uncertainties in Statistics Computed from DNS
Creators: name: Oliver, Todd A.
name: Malaya, Nicholas
name: Ulerich, Rhys
name: Moser, Robert D.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Fluid Dynamics (physics.flu-dyn)
subject: Chaotic Dynamics (nlin.CD)
subject: Computational Physics (physics.comp-ph)
subject: FOS: Physical sciences

description: Rigorous assessment of uncertainty is crucial to the utility of DNS results. Uncertainties in the computed statistics arise from two sources: finite statistical sampling and the discretization of the Navier-Stokes equations. Due to the presence of non-trivial sampling error, standard techniques for estimating discretization error (such as Richardson extrapolation) fail or are unreliable. This work provides a systematic and unified approach for estimating these errors. First, a sampling error estimator that accounts for correlation in the input data is developed. Then, this sampling error estimate is used as part of a Bayesian extension of Richardson extrapolation in order to characterize the discretization error. These methods are tested using the Lorenz equations and are shown to perform well. These techniques are then used to investigate the sampling and discretization errors in the DNS of a wall-bounded turbulent flow. For both cases, it is found that while the sampling uncertainty is large enough to make the order of accuracy difficult to determine, the estimated discretization errors are quite small. This indicates that the commonly used heuristics provide ad- equate resolution for this class of problems. However, it is also found that, for some quantities, the discretization error is not small relative to sampling error, indicating that the conventional wisdom that sampling error dominates discretization error for this class of simulations needs to be reevaluated.
description: 42 Pages, 17 Figures, Submitted to Physics of Fluids
Charged Higgs Discovery in the W plus "Dark" Vector Boson Decay Mode
Creators: name: Davoudiasl, Hooman
name: Marciano, William J.
name: Ramos, Raymundo
name: Sher, Marc
Publisher: name: arXiv
Year: 2014
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: In Two Higgs doublet extensions of the Standard Model, flavor-changing neutral current constraints can be addressed by introducing a U(1)' gauge symmetry, under which the Higgs doublets carry different charges. That scenario implies the presence of a H^\pm W^\mp Z' vertex at tree level. For the light "dark" Z model (Z'=Z_d) with m_{Z_d} < 10 GeV, such a coupling leads to the dominant decay mode H^\pm \to W^\pm + Z_d (for m_{H^\pm} \lsim 175 GeV), rather than the usual type I model decay H^\pm \to τ^\pm ν, for a broad range of parameters. We find that current analyses do not place significant bounds on this scenario. Over much of the parameter space considered, the decay of a pair-produced t ({\bar t}) into H^+ b (H^- {\bar b}) provides the dominant H^\pm production. Analysis of available LHC data can likely cover significant ranges of our parameters, if Z_d \to μ^+μ^- has a branching ratio of \sim 20%. If the Z_d decays mainly invisibly then probing the entire relevant parameter space would likely require additional data from future LHC runs. We briefly discuss the phenomenology for m_{H^\pm}\gsim 175 GeV.
description: 5 pages. New material on production of the charged Higgs in t tbar and in association with a top quark, as well as some references, added
From the Physics of Interacting Polymers to Optimizing Routes on the London Underground
Creators: name: Yeung, Chi Ho
name: Saad, David
name: Wong, K. Y. Michael
Publisher: name: arXiv
Year: 2013
Subjects: subject: Physics and Society (physics.soc-ph)
subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Networking and Internet Architecture (cs.NI)
subject: Adaptation and Self-Organizing Systems (nlin.AO)
subject: FOS: Physical sciences
subject: FOS: Computer and information sciences

description: Optimizing paths on networks is crucial for many applications, from subway traffic to Internet communication. As global path optimization that takes account of all path-choices simultaneously is computationally hard, most existing routing algorithms optimize paths individually, thus providing sub-optimal solutions. We employ the physics of interacting polymers and disordered systems to analyze macroscopic properties of generic path-optimization problems and derive a simple, principled, generic and distributed routing algorithm capable of considering simultaneously all individual path choices. We demonstrate the efficacy of the new algorithm by applying it to: (i) random graphs resembling Internet overlay networks; (ii) travel on the London underground network based on Oyster-card data; and (iii) the global airport network. Analytically derived macroscopic properties give rise to insightful new routing phenomena, including phase transitions and scaling laws, which facilitate better understanding of the appropriate operational regimes and their limitations that are difficult to obtain otherwise.
description: 6 pages, 6 figures. Supplementary information available at: http://www.pnas.org/content/suppl/2013/07/29/1301111110.DCSupplemental
Novel considerations about the error budget of the LAGEOS-based tests of frame-dragging with GRACE geopotential models
Creators: name: Iorio, Lorenzo
name: Ruggiero, Matteo Luca
name: Corda, Christian
Publisher: name: arXiv
Year: 2013
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: Geophysics (physics.geo-ph)
subject: Space Physics (physics.space-ph)
subject: FOS: Physical sciences

description: A realistic assessment of the uncertainties in the even zonals of a given geopotential model must be made by directly comparing its coefficients with those of a wholly independent solution of superior formal accuracy. Otherwise, a favorable selective bias is introduced in the evaluation of the total error budget of the LAGEOS-based Lense-Thirring tests yielding likely too optimistic figures for it. By applying a novel approach which recently appeared in the literature, the second (L = 4) and the third (L = 6) even zonals turn out to be uncertain at a 2-3 10^-11 (L = 4) and 3-4 10^-11 (L = 6) level, respectively, yielding a total gravitational error of about 27-28%, with an upper bound of 37-39%. The results by Ries et al. themselves yield an upper bound for it of about 33%. The low-degree even zonals are not exclusively determined from the GRACE Satellite-to-Satellite Tracking (SST) range since they affect it with long-period, secular-like signatures over orbital arcs longer than one orbital period: GRACE SST is not accurately sensitive to such signals. Conversely, general relativity affects it with short-period effects as well. Thus, the issue of the a priori "imprinting" of general relativity itself in the GRACE-based models used so far remains open.
description: LaTex2e, 18 pages, 2 tables, no figures. Version matching the published one
Simulations of cosmic rays in large-scale structures: numerical and physical effects
Creators: name: Vazza, Franco
name: Gheller, Claudio
name: Brüggen, Marcus
Publisher: name: arXiv
Year: 2014
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: Non-thermal (relativistic) particles are injected into the cosmos by structure formation shock waves, active galactic nuclei and stellar explosions. We present a suite of unigrid cosmological simulations (up to $2048^3$) using a two-fluid model in the grid code ENZO. The simulations include the dynamical effects of cosmic-ray (CR) protons and cover a range of theoretically motivated acceleration efficiencies. For the bulk of the cosmic volume the modelling of CR processes is rather stable with respect to resolution, provided that a minimum (cell) resolution of $\approx 100 ~\rm kpc/h$ is employed. However, the results for the innermost cluster regions depend on the assumptions for the baryonic physics. Inside clusters, non-radiative runs at high resolution tend to produce an energy density of CRs that are below available upper limits from the FERMI satellite, while the radiative runs are found to produce a higher budget of CRs. We show that weak ($M \leq 3-5$) shocks and shock-reacceleration are crucial to set the level of CRs in the innermost region of clusters, while in the outer regions the level of CR energy is mainly set via direct injection by stronger shocks, and is less sensitive to cooling and feedback from active galactic nuclei and supernovae.
description: 17 pages, 12 figures. MNRAS accepted. Movies of the largest 2048^3 run can be found here http://www.youtube.com/user/cosmofra
Dust Scattering In Turbulent Media: Correlation Between The Scattered Light and Dust Column Density
Creators: name: Seon, Kwang-Il
name: Witt, Adolf N.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: Radiative transfer models in a spherical, turbulent interstellar medium (ISM) in which the photon source is situated at the center are calculated to investigate the correlation between the scattered light and the dust column density. The medium is modeled using fractional Brownian motion structures that are appropriate for turbulent ISM. The correlation plot between the scattered light and optical depth shows substantial scatter and deviation from simple proportionality. It was also found that the overall density contrast is smoothed out in scattered light. In other words, there is an enhancement of the dust-scattered flux in low-density regions, while the scattered flux is suppressed in high-density regions. The correlation becomes less significant as the scattering becomes closer to be isotropic and the medium becomes more turbulent. Therefore, the scattered light observed in near-infrared wavelengths would show much weaker correlation than the observations in optical and ultraviolet wavelengths. We also find that the correlation plot between scattered lights at two different wavelengths shows a tighter correlation than that of the scattered light versus the optical depth.
description: 6 pages, 5 figure, accepted for publication in the ApJ Letters
Search for Majoron at the COMET Experiment
Creators: name: Xing, Tianyu
name: Wu, Chen
name: Miao, Han
name: Li, Hai-Bo
name: Li, Weiguo
name: Yuan, Ye
name: Zhang, Yao
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Experiment (hep-ex)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: A new Goldstone particle named Majoron is introduced in order to explain the origin of neutrino mass by some new physics models assuming that neutrinos are Majorana particle. By expanding signal region and using likelihood analysis, it becomes possible to search for Majoron at experiments that is originally designed to search for $μ-e$ conversion. For the COMET experiment, the sensitivity of process $μ\rightarrow eJ$ is able to reach ${\mathcal{B}}(μ\rightarrow eJ)=2.3\times 10^{-5}$ in Phase-I and $O(10^{-8})$ in Phase-II. Meanwhile, the sensitivities to search for Majoron at future experiments are also discussed in this article.
description: 8 pages, 10 figures, 3 tables
An Innate Motivation to Tidy Your Room: Online Onboard Evolution of Manipulation Behaviors in a Robot Swarm (plots and video)
Creators: name: Kaiser, Tanja Katharina
name: Lang, Christine
name: Marwitz, Florian Andreas
name: Charles, Christian
name: Dreier, Sven
name: Petzold, Julian
name: Hannawald, Max Ferdinand
name: Begemann, Marian Johannes
name: Hamann, Heiko
Publisher: name: Zenodo
Year: 2020

description: As our contribution to the effort of developing methods to make robots more adaptive and robust to dynamic environments, we have proposed our method of 'minimal surprise' in a series of previous works. In a multi-robot setting, we use evolutionary computation to evolve pairs of artificial neural networks: an actor network to select motor speeds and a predictor network to predict future sensor input. By rewarding for prediction accuracy, we give robots an innate motivation to behave in structured and thus, predictable ways. While we previously focused on feasibility studies using abstract simulations, we now present our first results using realistic robot simulations and first experiments with real robot hardware. In a centralized online and onboard evolution approach, we show that minimize surprise works effectively on Thymio II robots in a box-pushing scenario.
Ionospheric observations of Underground Nuclear Explosions (UNE) using GPS and the Very Large Array
Creators: name: Park, Jihye
name: Helmboldt, Joseph
name: Grejner-Brzezinska, Dorota A.
name: von Frese, Ralph R. B.
name: Wilson, Thomas
Publisher: name: arXiv
Year: 2013
Subjects: subject: Space Physics (physics.space-ph)
subject: FOS: Physical sciences

description: Observations from GPS receivers and the Very Large Array (VLA) radio telescope recorded traveling ionospheric disturbances (TID) from underground nuclear explosions (UNEs), detonated in September 1992. The slant TEC (STEC) data derived from GPS observations were processed for all ray paths to isolate TIDs. For the TIDs from the Hunters Trophy test on 18 September 1992 and the Divider test on 23 September 1992, the propagated mean velocities of the TIDs were about 573m/s and 740m/s with standard deviations of 85m/s and 135 m/s, respectively. For the VLA observations, the spectral analysis produced three-dimensional fluctuation spectral cubes for the Hunters Trophy event. The arrival time of the TID at the VLA implied a propagation speed of 570-710 m/s. This study suggests the global availability of GNSS tracking networks and new low-frequency (VHF) radio telescopes may offer a method of UNE detection and characterization, which could complement the International Monitoring System (IMS).
description: accepted for publication in Radio Science
Dynamics and Separation of Circularly Moving Particles in Asymmetric Patterned Arrays
Creators: name: Reichhardt, C.
name: Reichhardt, C. J. Olson
Publisher: name: arXiv
Year: 2013
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Soft Condensed Matter (cond-mat.soft)
subject: FOS: Physical sciences

description: There are many examples of driven and active matter systems containing particles that exhibit circular motion with different chiralities, such as swimming bacteria near surfaces or certain types of self-driven colloidal particles. Circular motion of passive particles can also be induced with an external rotating drive. Here we examine particles that move in circles and interact with a periodic array of asymmetric L-shaped obstacles. We find a series of dynamical phases as a function of swimming radius, including regimes where the particle motion is rectified, producing a net dc motion. The direction of the rectification varies with the swimming radius, permitting the separation of particles with different swimming radii. Particles with the same swimming radius but different chirality can also move in different directions over the substrate and be separated. The rectification occurs for specific windows of swimming radii corresponding to periodic orbits in which the particles interact one or more times with the barriers per rotation cycle. The rectification effects are robust against the addition of thermal or diffusive effects, and are in some cases even enhanced by these effects.
description: 10 pages, 15 postscript figures
Tug-the-hook symmetry for quantum 6j-symbols
Creators: name: Lanina, E.
name: Sleptsov, A.
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Mathematical Physics (math-ph)
subject: Quantum Algebra (math.QA)
subject: Representation Theory (math.RT)
subject: FOS: Physical sciences
subject: FOS: Mathematics

description: We introduce a novel symmetry for quantum 6j-symbols, which we call the tug-the-hook symmetry. Unlike other known symmetries, it is applicable for any representations, including ones with multiplicities. We provide several evidences in favour of the tug-the-hook symmetry. First, this symmetry follows from the eigenvalue conjecture. Second, it is shown by several new examples of explicit coincidence of 6j-symbols with multiplicities. Third, the tug-the-hook symmetry for Wilson loops for knots in the 3d Chern-Simons theory implies the tug-the-hook symmetry for quantum 6j-symbols. An important implication of the analysis is the generalization of the tug-the-hook symmetry for the Chern-Simons Wilson loops to the case of links.
description: 12 pages, published version
Uniformly Movable Categories And Uniform Movability Of Topological Spaces
Creators: name: Gevorgyan, Pavel S.
name: Pop, I.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Algebraic Topology (math.AT)
subject: General Topology (math.GN)
subject: FOS: Mathematics
subject: 54C56, 55P55, 18A25

description: A categorical generalization of the notion of movability from the inverse systems and shape theory was given by the first author who defined the notion of movable category and interpreted by this the movability of topological spaces. In this paper the authors define the notion of uniformly movable category and prove that a topological space is uniformly movable in the sense of the shape theory if and only if its comma category in the homotopy category HTop over the subcategory HPol of polyhedra is a uniformly movable category. This is a weakened version of the categorical notion of uniform movability introduced by the second author.
description: 12 pages
title: An Exploration of the Influence of Recreation Benefits and Use of Public Parks: The Impact on Sense of Community in Neighborhoods
Creators: name: Gueorguiev, Svetoslav Dimov
Publisher: name: Old Dominion University
publisherIdentifier: https://ror.org/04zjtrb98
publisherIdentifierScheme: ROR
Year: 2007

description: The purpose of the present study was to explore what influence public parks have on the sense of community of the residents living near parks. Respondents were chosen from within the service area (0.5 miles) of five parks in Norfolk, VA They rated their park experiences and answered sense of community and demographic questions. Confirmatory factor analysis identified five different dimensions in measuring the SOC levels. Correlation and regression analyses identified the extent of the influence that recreation participation had on sense of community of residents. Results confirmed that recreation use of parks positively influences SOC. Due to the existence of physical barriers such as major roads, a comparison of the means analysis (independent sample/test) of SOC levels in residents of areas adjacent to a park and of areas separated by a barrier was conducted. Results indicated a significant difference of the SOC level in the two groups. As a result of a the large number of people not using public parks, a comparison of mean analysis was conducted to reveal the extent to which the two groups differ m their SOC level. The results indicated a significant difference between users and non-users, with significantly higher SOC levels reported by the users. The results of the present study were then discussed in the context of previous research on SOC and recreation benefits of park use. Conclusions about the effects that public parks have on SOC were made and possible areas of related future research were proposed.
Nonlinear dynamics of trapped waves on jet currents and rogue waves
Creators: name: Shrira, Victor
name: Slunyaev, Alexey
Publisher: name: arXiv
Year: 2014
Subjects: subject: Fluid Dynamics (physics.flu-dyn)
subject: Geophysics (physics.geo-ph)
subject: FOS: Physical sciences

description: Nonlinear dynamics of surface gravity waves trapped by an opposing jet current is studied analytically and numerically. For wave fields narrowband in frequency but not necessarily with narrow angular distributions the developed asymptotic weakly nonlinear theory based on the modal approach of (V. Shrira, A. Slunyaev, J. Fluid. Mech, 738, 65, 2014) leads to the one-dimensional modified nonlinear Schrödinger equation of self-focusing type for a single mode. Its solutions such as envelope solitons and breathers are considered to be prototypes of rogue waves; these solutions, in contrast to waves in the absence of currents, are robust with respect to transverse perturbations, which suggests potentially higher probability of rogue waves. Robustness of the long-lived analytical solutions in form of the modulated trapped waves and solitary wave groups is verified by direct numerical simulations of potential Euler equations.
description: 4 pages, 2 figures, 3 movies (supplemental materials, not enclosed to this submission)
Diagonal Tau-Functions of 2D Toda Lattice Hierarchy, Connected $(n,m)$-Point Functions, and Double Hurwitz Numbers
Creators: name: Wang, Zhiyuan
name: Yang, Chenglang
Publisher: name: arXiv
Year: 2022
Subjects: subject: Exactly Solvable and Integrable Systems (nlin.SI)
subject: Mathematical Physics (math-ph)
subject: Algebraic Geometry (math.AG)
subject: Combinatorics (math.CO)
subject: FOS: Physical sciences
subject: FOS: Mathematics

description: We derive an explicit formula for the connected $(n,m)$-point functions associated to an arbitrary diagonal tau-function $τ_f(\boldsymbol{t}^+,\boldsymbol{t}^-)$ of the 2d Toda lattice hierarchy using fermionic computations and the boson-fermion correspondence. Then for fixed $\boldsymbol{t}^-$, we compute the KP-affine coordinates of $τ_f(\boldsymbol{t}^+,\boldsymbol{t}^-)$. As applications, we present a unified approach to compute various types of connected double Hurwitz numbers, including the ordinary double Hurwitz numbers, the double Hurwitz numbers with completed $r$-cycles, and the mixed double Hurwitz numbers. We also apply this method to the computation of the stationary Gromov-Witten invariants of $\mathbb P^1$ relative to two points.
On the decay of elements of inverse triangular Toeplitz matrix
Creators: name: Ford, Neville
name: Savostyanov, D. V.
name: Zamarashkin, N. L.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Numerical Analysis (math.NA)
subject: Classical Analysis and ODEs (math.CA)
subject: FOS: Mathematics
subject: 15A09, 15B05, 45E10

description: We consider half-infinite triangular Toeplitz matrices with slow decay of the elements and prove under a monotonicity condition that elements of the inverse matrix, as well as elements of the fundamental matrix, decay to zero. We also provide a quantitative description of the decay of the fundamental matrix in terms of p-norms. Finally, we prove that for matrices with slow log-convex decay the inverse matrix has fast decay, i.e. is bounded. The results are compared with the classical results of Jaffard and Veccio and illustrated by numerical example.
Geometric Thermoelectric Pump: Energy Harvesting beyond Seebeck and Pyroelectric Effects
Creators: name: Ren, Jie
Publisher: name: arXiv
Year: 2014
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Materials Science (cond-mat.mtrl-sci)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: Thermal-electric conversion is crucial for smart energy control and harvesting, such as thermal sensing and waste heat recovering. So far, people are aware of two main ways of direct thermal-electric conversion, Seebeck and pyroelectric effects, each with different working mechanisms, conditions and limitations. Here, we report the concept of "Geometric Thermoelectric Pump", as the third way of thermal-electric conversion beyond Seebeck and pyroelectric effects. In contrast to Seebeck effect that requires spatial temperature difference, Geometric Thermoelectric Pump converts the time-dependent ambient temperature fluctuation into electricity. Moreover, Geometric Thermoelectric Pump does not require polar materials but applies to general conducting systems, thus is also distinct from pyroelectric effect. We demonstrate that Geometric Thermoelectric Pump results from the temperature-fluctuation-induced charge redistribution, which has a deep connection to the topological geometric phase in non-Hermitian dynamics, as a consequence of the fundamental nonequilibrium thermodynamic geometry. The findings advance our understanding of geometric phase induced multiple-physics-coupled pump effect and provide new means of thermal-electric energy harvesting.
description: 7 pages, 4 figures, accepted by Chin. Phys. Lett. See https://doi.org/10.1088/0256-307X/40/9/090501
Consistent Causal Inference from Time Series with PC Algorithm and its Time-Aware Extension
Creators: name: Biswas, Rahul
name: Mukherjee, Somabha
Publisher: name: arXiv
Year: 2022
Subjects: subject: Methodology (stat.ME)
subject: Applications (stat.AP)
subject: FOS: Computer and information sciences

description: The estimator of a causal directed acyclic graph (DAG) with the PC algorithm is known to be consistent based on independent and identically distributed samples. In this paper, we consider the scenario when the multivariate samples are identically distributed but not independent. A common example is a stationary multivariate time series. We show that under a standard set of assumptions on the underlying time series involving $ρ$-mixing, the PC algorithm is consistent in this dependent sample scenario. Further, we show that for the popular time series models such as vector auto-regressive moving average and linear processes, consistency of the PC algorithm holds. We also prove the consistency for the Time-Aware PC algorithm, a recent adaptation of the PC algorithm for the time series scenario. Our findings are supported by simulations and benchmark real data analyses provided towards the end of the paper.
Interaction-free all-optical switching at low light Intensities in a multi-atom cavity QED system
Creators: name: Zou, Bichen
name: Tan, Zheng
name: Musa, Mohamed
name: Zhu, Yifu
Publisher: name: arXiv
Year: 2013
Subjects: subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: We propose a scheme of the interaction-free all-optical switching in a multi-atom cavity QED system consisting of three-level atoms confined in a cavity and coupled by a free-space control laser. A signal laser field is coupled into the cavity and its transmission through and reflection from the cavity form two output channels. We show that the free-space control laser induces destructive quantum interference in the excitation of the intra-cavity normal mode, which can be used to switch on or off of the output signal light of the reflection and the transmission channels. When the control light is coupled to the atoms, the input signal light is nearly totally reflected and this means that there is no direct coupling of the control light and the signal light through the cavity-confined atoms. We present analytical and numerical calculations that show this type of the interaction-free all-optical switching in the coupled cavity-atom system can be realized with high switching efficiencies and at low light intensities.
description: 19 pages, 8 figures
Intellectual and Immaterial Bank (IIB) as a computational humor-based change agent
Creators: name: Zaytseva, Anna
Publisher: name: Zenodo
Year: 2020
Subjects: transformation
humor
computational change agent
symmetry
hybrid competence
collaboration
professional
distributed architecture
self-organization

description: IIB is a computational, humor-based change agent as a science-driven digital solution for so-called "cultures of failure" that are: - the collaborative environments that treat failure as new, real-world data, and make it work for their successful transformative adaptation to the new, and, therefore, can make the new; - the individual professionals, who tend to notice a bit more than the others, dare to speak up and fail, but mistakenly think of themselves as failures – those are, in fact, key to competitive advantage of the collaborative environments ...were no unnecessary information – any facial data unrelated to being capable, or needing a change – is ever shown, and the data belongs to the user that has actively generated it ...where both sides of the interaction – persons and collaborative environments – are treated in symmetry for facilitation of their spontaneous, imperfect, but stimulating self-organization Challenge the creator at this address: annza944@gmail.com
description: Funded by Innovation Norway
RKKY interaction in one-dimensional flat-band lattices
Creators: name: Laubscher, Katharina
name: Weber, Clara S.
name: Hünenberger, Maximilian
name: Schoeller, Herbert
name: Kennes, Dante M.
name: Loss, Daniel
name: Klinovaja, Jelena
Publisher: name: arXiv
Year: 2022
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: We study the Ruderman-Kittel-Kasuya-Yosida (RKKY) interaction between two classical magnetic impurities in one-dimensional lattice models with flat bands. As two representative examples, we pick the stub lattice and the diamond lattice at half filling. We first calculate the exact RKKY interaction numerically and then compare our data to results obtained via different analytical techniques. In both our examples, we find that the RKKY interaction exhibits peculiar features that can directly be traced back to the presence of a flat band in the energy spectrum. Importantly, these features are not captured by the conventional RKKY approximation based on non-degenerate perturbation theory. Instead, we find that degenerate perturbation theory correctly reproduces our exact results if there is an energy gap between the flat and the dispersive bands, while a non-perturbative approach becomes necessary in the absence of a gap.
МЕТОДИКА СБОРА, ОЦЕНКИ И ВЫБОРА ИННОВАЦИЙ: ПЕРСПЕКТИВЫ РЕАЛИЗАЦИИ
Creators: name: САРКИСЯН Д.А.
name: ЛЯСКОВСКИЙ В.Л.
Publisher: name: Компетентность
Year: 2020
Subjects: ТАКТИКО-ТЕХНИЧЕСКИЕ ХАРАКТЕРИСТИКИ
РЕЗУЛЬТАТЫ ИННОВАЦИОННЫХ ТЕОРЕТИЧЕСКИХ ИССЛЕДОВАНИЙ
РИСКИ РЕАЛИЗАЦИИ
tactical and technical characteristics
results of innovative theoretical research
implementation risks

description: Решается задача отбора инноваций для их реализации в перспективных образцах вооружения, военной и специальной техники. Используются методы диссенсусного подхода как способ получения экспертных оценок. Рассматривается пример реализации предложенной методики
description: We have studied and solved the problem of selecting innovations for their further implementation in promising models of weapons, military and special equipment. At the same time, we took into account such parameters as the main tactical and technical characteristics of the samples and the influence degree of innovations on them, the sample type importance and possible risks of implementation. We suggested using the dissensual approach as a way to obtain expert assessments. We considered an example of the implementation of the proposed methodology.
Efficiency Measurements and Installation of a New Grating for the OSIRIS Spectrograph at Keck Observatory
Creators: name: Mieda, Etsuko
name: Wright, Shelley A.
name: Larkin, James E.
name: Graham, James R.
name: Adkins, Sean M.
name: Lyke, James E.
name: Campbell, Randy D.
name: Maire, Jerome
name: Do, Tuan
name: Gordon, Jacob
Publisher: name: arXiv
Year: 2014
Subjects: subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: FOS: Physical sciences

description: OSIRIS is a near-infrared integral field spectrograph operating behind the adaptive optics system at W. M. Keck Observatory. While OSIRIS has been a scientifically productive instrument to date, its sensitivity has been limited by a grating efficiency that is less than half of what was expected. The spatially averaged efficiency of the old grating, weighted by error, is measured to be 39.5 +/- 0.8 % at λ = 1.310 μm, with large field dependent variation of 11.7 % due to efficiency variation across the grating surface. Working with a new vendor, we developed a more efficient and uniform grating with a weighted average efficiency at λ = 1.310 μm of 78.0 +/- 1.6 %, with field variation of only 2.2 %. This is close to double the average efficiency and five times less variation across the field. The new grating was installed in December 2012, and on- sky OSIRIS throughput shows an average factor of 1.83 improvement in sensitivity between 1 and 2.4 microns. We present the development history, testing, and implementation of this new near-infrared grating for OSIRIS and report the comparison with the predecessors. The higher sensitivities are already having a large impact on scientific studies with OSIRIS.
Source code of numerical model used in Kawai and Tomita (2023)
Creators: name: Kawai, Yuta
Publisher: name: Zenodo
Year: 2023
Subjects: Large-Eddy Simulation, Discontinuous Galerkin Method, Numerical Accuracy

description: This archive contains source codes of numerical models and input files used in the paper "Numerical Accuracy Necessary for Large-Eddy Simulation of Planetary Boundary Layer Turbulence using Discontinuous Galerkin Method." by Kawai and Tomita. The codes to analyze the simulation results are also contained.
description: The latest version of our atmospheric model based on DGM can be obtained from a github repository. Please see https://github.com/ywkawai/FE-Project.
Wave front adaptation using a deformable mirror for adiabatic nanofocusing along an ultrasharp gold taper
Creators: name: Schmidt, Slawa
name: Engelke, Pascal
name: Piglosiewicz, Bjoern
name: Esmann, Martin
name: Becker, Simon F.
name: Yoo, Kyungwan
name: Park, Namkyoo
name: Lienau, Christoph
name: Gross, Petra
Publisher: name: arXiv
Year: 2013
Subjects: subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: We describe and demonstrate the use of an adaptive wave front optimization scheme for enhancing the efficiency of adiabatic nanofocusing of surface plasmon polariton (SPP) waves along an ultrasharp conical gold taper. Adiabatic nanofocusing is an emerging and promising scheme for controlled focusing of far field light into nanometric volumes. It comprises three essential steps: SPP excitation by coupling far field light to an SPP waveguide, SPP propagation along the waveguide and adiabatic SPP nanofocusing towards a geometric singularity. For commonly used complex waveguide geometries, such as, e.g., conical metal tapers, a realistic modeling and efficiency optimization is challenging. Here, we use a deformable mirror to adaptively control the wave front of the incident far field light. We demonstrate an eight-fold enhancement in nanofocusing efficiency and analyze the shape of the resulting optimized wave front. The introduced wave front optimization scheme is of general interest for guiding and controlling light on the nanoscale.
Bayer-Macrì decomposition on Bridgeland moduli spaces over surfaces
Creators: name: Liu, Wanmin
Publisher: name: arXiv
Year: 2015
Subjects: subject: Algebraic Geometry (math.AG)
subject: FOS: Mathematics
subject: 14D20, (Primary), 18E30, 14E30 (Secondary)

description: We find a decomposition formula of the local Bayer-Macrì map for the nef line bundle theory on the Bridgeland moduli space over surface. If there is a global Bayer-Macrì map, such decomposition gives a precise correspondence from Bridgeland walls to Mori walls. As an application, we compute the nef cone of the Hilbert scheme $S^{[n]}$ of $n$-points over special kinds of fibered surface $S$ of Picard rank two.
description: 23 pages
On calculating the slice genera of 11- and 12-crossing knots
Creators: name: Lewark, Lukas
name: McCoy, Duncan
Publisher: name: arXiv
Year: 2015
Subjects: subject: Geometric Topology (math.GT)
subject: FOS: Mathematics

description: This paper contains the results of efforts to determine values of the smooth and the topological slice genus of 11- and 12-crossing knots. Upper bounds for these genera were produced by using a computer to search for genus one concordances between knots. For the topological slice genus further upper bounds were produced using the algebraic genus. Lower bounds were obtained using a new obstruction from the Seifert form and by use of Donaldson's diagonalization theorem. These results complete the computation of the topological slice genera for all knots with at most 11 crossings and leaves the smooth genera unknown for only two 11-crossing knots. For 12 crossings there remain merely 25 knots whose smooth or topological slice genus is unknown.
description: 12 pages + 11 pages of appendices. v2: This is a substantial expansion of the original article. This version features a second author and new techniques for calculating the topological slice genus. v3: Fixed some mistakes (all computed values remain valid), and computed some additional values
Dynamics of Boolean Networks
Creators: name: Zou, Yi Ming
Publisher: name: arXiv
Year: 2013
Subjects: subject: Quantitative Methods (q-bio.QM)
subject: FOS: Biological sciences

description: Boolean networks are special types of finite state time-discrete dynamical systems. A Boolean network can be described by a function from an n-dimensional vector space over the field of two elements to itself. A fundamental problem in studying these dynamical systems is to link their long term behaviors to the structures of the functions that define them. In this paper, a method for deriving a Boolean network's dynamical information via its disjunctive normal form is explained. For a given Boolean network, a matrix with entries 0 and 1 is associated with the polynomial function that represents the network, then the information on the fixed points and the limit cycles is derived by analyzing the matrix. The described method provides an algorithm for the determination of the fixed points from the polynomial expression of a Boolean network. The method can also be used to construct Boolean networks with prescribed limit cycles and fixed points. Examples are provided to explain the algorithm.
Power-law distributions for the free path length in Lorentz gases
Creators: name: Marklof, Jens
name: Strömbergsson, Andreas
Publisher: name: arXiv
Year: 2013
Subjects: subject: Mathematical Physics (math-ph)
subject: Dynamical Systems (math.DS)
subject: FOS: Physical sciences
subject: FOS: Mathematics

description: It is well known that, in the Boltzmann-Grad limit, the distribution of the free path length in the Lorentz gas with disordered scatterer configuration has an exponential density. If, on the other hand, the scatterers are located at the vertices of a Euclidean lattice, the density has a power-law tail proportional to xi^{-3}. In the present paper we construct scatterer configurations whose free path lengths have a distribution with tail xi^{-N-2} for any positive integer N. We also discuss the properties of the random flight process that describes the Lorentz gas in the Boltzmann-Grad limit. The convergence of the distribution of the free path length follows from equidistribution of large spheres in products of certain homogeneous spaces, which in turn is a consequence of Ratner's measure classification theorem.
description: 13 pages
An uncertainty principle for star formation. I. Why galactic star formation relations break down below a certain spatial scale
Creators: name: Kruijssen, J. M. Diederik
name: Longmore, Steven N.
Publisher: name: arXiv
Year: 2014
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: Galactic scaling relations between the (surface densities of) the gas mass and the star formation (SF) rate are known to develop substantial scatter or even change form when considered below a certain spatial scale. We quantify how this behaviour should be expected due to the incomplete statistical sampling of independent star-forming regions. Other included limiting factors are the incomplete sampling of SF tracers from the stellar initial mass function and the spatial drift between gas and stars. We present a simple uncertainty principle for SF, which can be used to predict and interpret the failure of galactic SF relations on small spatial scales. This uncertainty principle explains how the scatter of SF relations depends on the spatial scale and predicts a scale-dependent bias of the gas depletion time-scale when centering an aperture on gas or SF tracer peaks. We show how the scatter and bias are sensitive to the physical size and time-scales involved in the SF process (such as its duration or the molecular cloud lifetime), and illustrate how our formalism provides a powerful tool to constrain these largely unknown quantities. Thanks to its general form, the uncertainty principle can also be applied to other astrophysical systems, e.g. addressing the time-evolution of star-forming cores, protoplanetary discs, or galaxies and their nuclei.
description: 14 pages (including appendices), 5 figures, 2 tables; accepted by MNRAS (15 January 2014). Fortran and IDL routines for applying the uncertainty principle are publicly available at http://www.mpa-garching.mpg.de/KL14principle/
Jordan triple product homomorphisms on Hermitian matrices to and from dimension one
Creators: name: Bukovsek, Damjana Kokol
name: Mojskerc, Blaz
Publisher: name: arXiv
Year: 2015
Subjects: subject: Rings and Algebras (math.RA)
subject: Operator Algebras (math.OA)
subject: FOS: Mathematics
subject: 16W10, 16W20, 15B57

description: We characterise all Jordan triple product homomorphisms, that is, mappings $Φ$ satisfying $$ Φ(ABA) = Φ(A)Φ(B)Φ(A) $$ from the set of all Hermitian $n \times n$ complex matrices to the field of complex numbers. Further we characterise all Jordan triple product homomorphisms from the field of complex or real numbers or the set of all nonnegative real numbers to the set of all Hermitian $n \times n$ complex matrices.
description: 10 pages
A note on knot fertility II
Creators: name: Ito, Tetsuya
Publisher: name: arXiv
Year: 2022
Subjects: subject: Geometric Topology (math.GT)
subject: FOS: Mathematics

description: A knot $K$ is called $(m,n)$-fertile if for every prime knot $K'$ whose crossing number is less than or equal to $m$, there exists an $n$-crossing diagram of $K$ such that one can get $K'$ from the diagram by changing its over-under information. We give an obstruction for knot to be $(m,n)$-fertile. As application, we prove the finiteness of $(c(K)+f,c(K)+p)$-fertile knots for all $f,p$. We also discuss the nubmer of Seiefrt circle and writhe of minimum crossing diagrams.
description: 7 pages, no Figures
Multi-scale data reconstruction of turbulent rotating flows with Gappy POD, Extended POD and Generative Adversarial Networks
Creators: name: Li, Tianyi
name: Buzzicotti, Michele
name: Biferale, Luca
name: Bonaccorso, Fabio
name: Chen, Shiyi
name: Wan, Minping
Publisher: name: arXiv
Year: 2022
Subjects: subject: Fluid Dynamics (physics.flu-dyn)
subject: Computer Vision and Pattern Recognition (cs.CV)
subject: Machine Learning (cs.LG)
subject: Chaotic Dynamics (nlin.CD)
subject: Geophysics (physics.geo-ph)
subject: FOS: Physical sciences
subject: FOS: Computer and information sciences

description: Data reconstruction of rotating turbulent snapshots is investigated utilizing data-driven tools. This problem is crucial for numerous geophysical applications and fundamental aspects, given the concurrent effects of direct and inverse energy cascades, which lead to non-Gaussian statistics at both large and small scales. Data assimilation also serves as a tool to rank physical features within turbulence, by evaluating the performance of reconstruction in terms of the quality and quantity of the information used. Additionally, benchmarking various reconstruction techniques is essential to assess the trade-off between quantitative supremacy, implementation complexity, and explicability. In this study, we use linear and non-linear tools based on the Proper Orthogonal Decomposition (POD) and Generative Adversarial Network (GAN) for reconstructing rotating turbulence snapshots with spatial damages (inpainting). We focus on accurately reproducing both statistical properties and instantaneous velocity fields. Different gap sizes and gap geometries are investigated in order to assess the importance of coherency and multi-scale properties of the missing information. Surprisingly enough, concerning point-wise reconstruction, the non-linear GAN does not outperform one of the linear POD techniques. On the other hand, supremacy of the GAN approach is shown when the statistical multi-scale properties are compared. Similarly, extreme events in the gap region are better predicted when using GAN. The balance between point-wise error and statistical properties is controlled by the adversarial ratio, which determines the relative importance of the generator and the discriminator in the GAN training. Robustness against the measurement noise is also discussed.