cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Dynamic wrinkling and strengthening of a filament in a viscous fluid
Creators: name: Chopin, Julien
name: Dasgupta, Moumita
name: Kudrolli, Arshad
Publisher: name: arXiv
Year: 2017
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: FOS: Physical sciences

description: We investigate the wrinkling dynamics of an elastic filament immersed in a viscous fluid submitted to compression at a finite rate with experiments and by combining geometric nonlinearities, elasticity, and slender body theory. The drag induces a dynamic lateral reinforcement of the filament leading to growth of wrinkles that coarsen over time. We discover a new dynamical regime characterized by a timescale with a non-trivial dependence on the loading rate, where the growth of the instability is super-exponential and the wavenumber is an increasing function of the loading rate. We find that this timescale can be interpreted as the characteristic time over which the filament transitions from the extensible to the inextensible regime. In contrast with our analysis with moving boundary conditions, Biot's analysis in the limit of infinitely fast loading leads to rate independent exponential growth and wavelength.
Non-Universal and Universal Aspects of The Large Scattering Length Limit
Creators: name: Miller, Gerald A.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Nuclear Theory (nucl-th)
subject: Quantum Gases (cond-mat.quant-gas)
subject: Nuclear Experiment (nucl-ex)
subject: Atomic and Molecular Clusters (physics.atm-clus)
subject: Atomic Physics (physics.atom-ph)
subject: FOS: Physical sciences

description: The momentum density, $n(k)$ of interacting many-body Fermionic systems is studied (for $k>k_F)$ using examples of several well-known two-body interaction models. This work shows that $n(k)$ can not be approximated by a zero-range model for momenta $k$ greater than about $1/(a r_e^2)^{1/3}$, where $a$ is the scattering length, and $r_e$ the effective range. However, if the scattering length is large and one includes the effects of a fixed value of $r_e\ne0$, $n(k)$ is universal for momenta $k$ up to about $2/r_e$. An accurate relation between the energy of a two component Fermi-gas and an integral involving the density is derived. The short separation distance, $s$, behavior of the pair density is shown to vary as $s^6$.
description: 6 pages 2 figures. This version corrects several errors in the previous version. The analysis is deepened, and one conclusion is changed
How the huge energy of quantum vacuum gravitates to drive the slow accelerating expansion of the Universe
Creators: name: Wang, Qingdi
name: Zhu, Zhen
name: Unruh, William G.
Publisher: name: arXiv
Year: 2017
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We investigate the gravitational property of the quantum vacuum by treating its large energy density predicted by quantum field theory seriously and assuming that it does gravitate to obey the equivalence principle of general relativity. We find that the quantum vacuum would gravitate differently from what people previously thought. The consequence of this difference is an accelerating universe with a small Hubble expansion rate $H\propto Λe^{-β\sqrt{G}Λ}\to 0$ instead of the previous prediction $H=\sqrt{8πGρ^{vac}/3}\propto\sqrt{G}Λ^2\to\infty$ which was unbounded, as the high energy cutoff $Λ$ is taken to infinity. In this sense, at least the "old" cosmological constant problem would be resolved. Moreover, it gives the observed slow rate of the accelerating expansion as $Λ$ is taken to be some large value of the order of Planck energy or higher. This result suggests that there is no necessity to introduce the cosmological constant, which is required to be fine tuned to an accuracy of $10^{-120}$, or other forms of dark energy, which are required to have peculiar negative pressure, to explain the observed accelerating expansion of the Universe.
description: 35 pages, 8 figures, PRD Editors' Suggestion
The effect of magnetization and electric polarization on the anomalous transport coefficients of a chiral fluid
Creators: name: Sadooghi, N.
name: Tabatabaee, S. M. A.
Publisher: name: arXiv
Year: 2016
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: The effects of finite magnetization and electric polarization on dissipative and non-dissipative (anomalous) transport coefficients of a chiral fluid are studied. First, using the second law of thermodynamics as well as Onsager's time reversal symmetry principle, the complete set of dissipative transport coefficients of this medium is derived. It is shown that the properties of the resulting shear and bulk viscosities are mainly affected by the anisotropy induced by external electric and magnetic fields. Then, using the fact that the anomaly induced currents do not contribute to entropy production, the corresponding algebro-differential equations to non-dissipative anomalous transport coefficients are derived in a certain derivative expansion. The solutions of these equations show that, within this approximation, anomalous transport coefficients are, in particular, given in terms of the electric susceptibility of the medium.
description: V1: 14 pages (two-column), 1 table, no figure; V2: 20 pages (one-column), 1 table, no figure. Version accepted for publication in New Journal of Physics (2017)
Enhancement of crossed Andreev reflection in normal-superconductor-normal junction of thin topological insulator
Creators: name: Islam, SK Firoz
name: Dutta, Paramita
name: Saha, Arijit
Publisher: name: arXiv
Year: 2017
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: We theoretically investigate the subgapped transport phenomena through a normal-superconductor-normal (NSN) junction made up of ultra thin topological insulator with proximity induced superconductivity. The dimensional crossover from three dimensional ($3$D) topological insulator (TI) to thin two-dimensional ($2$D) TI introduces a new degree of freedom, the so-called hybridization or coupling between the two surface states. We explore the role of hybridization in transport properties of the NSN junction, especially how it affects the crossed Andreev reflection (CAR). We observe that a rib-like pattern appears in CAR probability profile while examined as a function of angle of incidence and length of the superconductor. Depending on the incoming and reflection or transmission channel, CAR probability can be maneuvered to be higher than $97\%$ under suitable coupling between the two TI surface states along with appropriate gate voltage and doping concentration in the normal region. Coupling between the two surfaces also induces an additional oscillation envelope in the behavior of the angle averaged conductance, with the variation of the length of the superconductor. The behavior of co-tunneling (CT) probability is also very sensitive to the coupling and other parameters. Finally, we also explore the shot noise cross correlation and show that the behavior of the same can be monotonic or non-monotonic depending on the doping concentration in the normal region. Under suitable circumstances, shot noise cross correlation can change sign from positive to negative or vice versa depending on the relative strength of CT and CAR.
description: This is the published version
An improved derivation of the Smarr Formula for Lorentz-breaking gravity
Creators: name: Pacilio, Costantino
name: Liberati, Stefano
Publisher: name: arXiv
Year: 2017
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: Thermodynamical properties of black holes in gravitational theories without Local Lorentz invariance have been subject to intense investigation in the past years due to the presence of universal horizons, which are strong causal barriers even for superluminal signals. Here we present a novel general method for deriving the Smarr formula for this class of theories: in particular we show that the Smarr formulae for Einstein-Aether theory and infrared Horava gravity follow from scale invariance. We not only reproduce straightforwardly previous findings for static black hole solutions, but we are also able to generalise them to the case of stationary rotating black holes. Finally, we apply our results to the rotating black holes with universal horizon as found in three dimensions, from which we shall draw some lessons on the viability of black hole thermodynamics for black hole solutions endowed with universal horizons.
description: 12 pages; v2: typos corrected, references added and updated, discussion improved; v3: minor typos corrected in Eqs (5) & (6)
Generalized Born-Infeld-like models for kinks and branes
Creators: name: Bazeia, D.
name: Marques, M. A.
name: Menezes, R.
Publisher: name: arXiv
Year: 2017
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: In this work we deal with a non-canonical scalar field in the two-dimensional spacetime. We search for a generalized model that is twin of the standard model, supporting the same defect structure with the same energy density. We also study the stability of the defect solution under small fluctuations, which is governed by a Sturm-Liouville equation, and show how to make it stable. The model is then modified and used in the five-dimensional spacetime to construct a thick brane that engenders the first order framework and preserves the twinlike behavior, under tensorial fluctuations of the metric in its gravitational sector.
description: 6 pages; v3, to appear in EPL
Dark Matter Search in a Proton Beam Dump with MiniBooNE
Creators: name: Aguilar-Arevalo, A. A.
name: Backfish, M.
name: Bashyal, A.
name: Batell, B.
name: Brown, B. C.
name: Carr, R.
name: Chatterjee, A.
name: Cooper, R. L.
name: deNiverville, P.
name: Dharmapalan, R.
name: Djurcic, Z.
name: Ford, R.
name: Garcia, F. G.
name: Garvey, G. T.
name: Grange, J.
name: Green, J. A.
name: Huelsnitz, W.
name: Astiz, I. L. de Icaza
name: Karagiorgi, G.
name: Katori, T.
name: Ketchum, W.
name: Kobilarcik, T.
name: Liu, Q.
name: Louis, W. C.
name: Marsh, W.
name: Moore, C. D.
name: Mills, G. B.
name: Mirabal, J.
name: Nienaber, P.
name: Pavlovic, Z.
name: Perevalov, D.
name: Ray, H.
name: Roe, B. P.
name: Shaevitz, M. H.
name: Shahsavarani, S.
name: Stancu, I.
name: Tayloe, R.
name: Taylor, C.
name: Thornton, R. T.
name: Van de Water, R.
name: Wester, W.
name: White, D. H.
name: Yu, J.
Publisher: name: arXiv
Year: 2017
Subjects: subject: High Energy Physics - Experiment (hep-ex)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: The MiniBooNE-DM collaboration searched for vector-boson mediated production of dark matter using the Fermilab 8 GeV Booster proton beam in a dedicated run with $1.86 \times 10^{20}$ protons delivered to a steel beam dump. The MiniBooNE detector, 490~m downstream, is sensitive to dark matter via elastic scattering with nucleons in the detector mineral oil. Analysis methods developed for previous MiniBooNE scattering results were employed, and several constraining data sets were simultaneously analyzed to minimize systematic errors from neutrino flux and interaction rates. No excess of events over background was observed, leading to a 90\% confidence limit on the dark-matter cross section parameter, $Y=ε^2α_D(m_χ/m_V)^4 \lesssim10^{-8}$, for $α_D=0.5$ and for dark-matter masses of $0.01
description: 6 pages, 7 figures, Version consistent with final PRL
Heun-type solutions for Schwarzschild metric with electromagnetic fields
Creators: name: Birkandan, T.
name: Hortaçsu, M.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Mathematical Physics (math-ph)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: We find confluent Heun solutions to the radial equations of two Halilsoy-Badawi metrics. For the first metric, we studied the radial part of the massless Dirac equation and for the second case, we studied the radial part of the massless Klein-Gordon equation.
description: 8 pages, 2 figures. Matches the published version
On HQET and NRQCD Operators of Dimension 8 and Above
Creators: name: Gunawardana, Ayesh
name: Paz, Gil
Publisher: name: arXiv
Year: 2017
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: Effective field theories such as Heavy Quark Effective Theory (HQET) and Non Relativistic Quantum Chromo-(Electro-) dynamics NRQCD (NRQED) are indispensable tools in controlling the effects of the strong interaction. The increasing experimental precision requires the knowledge of higher dimensional operators. We present a general method that allows for an easy construction of HQET or NRQCD (NRQED) operators that contain two heavy quark or non-relativistic fields and any number of covariant derivatives. As an application of our method, we list these terms in the $1/M^4$ NRQCD Lagrangian, where $M$ is the mass of of the spin-half field.
description: 28 pages, footnote added, journal version
Exact Boson Sampling using Gaussian continuous variable measurements
Creators: name: Lund, A. P.
name: Rahimi-Keshari, S.
name: Ralph, T. C.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: BosonSampling is a quantum mechanical task involving Fock basis state preparation and detection and evolution using only linear interactions. A classical algorithm for producing samples from this quantum task cannot be efficient unless the polynomial hierarchy of complexity classes collapses, a situation believe to be highly implausible. We present method for constructing a device which uses Fock state preparations, linear interactions and Gaussian continuous-variable measurements for which one can show exact sampling would be hard for a classical algorithm in the same way as Boson Sampling. The detection events used from this arrangement does not allow a similar conclusion for the classical hardness of approximate sampling to be drawn. We discuss the details of this result outlining some specific properties that approximate sampling hardness requires.
Quasi-diagonal Inhomogeneous Closure for Classical and Quantum Statistical Dynamics
Creators: name: Frederiksen, Jorgen S.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Fluid Dynamics (physics.flu-dyn)
subject: FOS: Physical sciences
subject: 76, 81, 82

description: The Quasi-diagonal Direct Interaction Approximation (QDIA) closure equations are formulated for inhomogeneous classical and quantum fields interacting through dynamical equations with quadratic nonlinearity and with first or second order time derivatives. Associated more complex inhomogeneous DIA and Self-Energy closure equations are expounded as part of the derivation. The QDIA employs a bare vertex approximation and is only a few times more computationally intensive than the homogeneous DIA. Examples of applications to turbulent classical geophysical and Navier Stokes fluids, including non-Gaussian noise, to classical and quantum Klein Gordon equations with g phi^3 Lagrangian interaction, and to coupled field-auxiliary field equations associated lambda phi^4 Lagrangian interaction, are presented.
description: 36 pages, no figures
Simplified D=11 Pure Spinor b Ghost
Creators: name: Berkovits, Nathan
name: Guillen, Max
Publisher: name: arXiv
Year: 2017
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: A $b$-ghost was constructed for the $D=11$ non-minimal pure spinor superparticle by requiring that $\{Q , b\} = T$ where $Q = Λ^αD_α + R^α\bar{W}_α$ is the usual non-minimal pure spinor BRST operator. As was done for the $D=10$ $b$-ghost, we will show that the $D=11$ $b$-ghost can be simplified by introducing an $SO(10,1)$ fermionic vector $\barΣ^{i}$ constructed out of the fermionic spinor $D_α$ and pure spinor variables. This simplified version will be shown to satisfy $\{Q, b\} = T$ and $\{b , b\} =$ BRST - trivial.
description: 47 pages. Added references
Low‐Pt NiNC‐Supported PtNi Nanoalloy Oxygen Reduction Reaction Electrocatalysts—In Situ Tracking of the Atomic Alloying Process
Creators: name: Feng, Quanchen
name: Wang, Xingli
name: Klingenhof, Malte
name: Heggen, Marc
name: Strasser, Peter
Publisher: name: Technische Universität Berlin
Year: 2022
Subjects: subject: 540 Chemie und zugeordnete Wissenschaften
subject: atomic alloying process
subject: bimetallic nanocatalyst
subject: oxygen reduction reaction
subject: polymer electrolyte membrane fuel cell
subject: structure–activity relationship

description: We report and analyze a synthetic strategy toward low‐Pt platinum‐nickel (Pt‐Ni) alloy nanoparticle (NP) cathode catalysts for the catalytic electroreduction of molecular oxygen to water. The synthesis involves the pyrolysis and leaching of Ni‐organic polymers, subsequent Pt NP deposition, followed by thermal alloying, resulting in single Ni atom site (NiNC)‐supported PtNi alloy NPs at low Pt weight loadings of only 3–5 wt %. Despite low Pt weight loading, the catalysts exhibit more favorable Pt‐mass activities compared to conventional 20–30 wt % benchmark PtNi catalysts. Using in situ microscopic techniques, we track and unravel the key stages of the PtNi alloy formation process directly at the atomic scale. Surprisingly, we find that carbon‐encapsulated metallic Ni@C structures, rather than NiNx sites, act as the Ni source during alloy formation. Our materials concepts offer a pathway to further decrease the overall Pt content in hydrogen fuel cell cathodes.
First Light: exploring the Spectra of High-Redshift Galaxies in the Renaissance Simulations
Creators: name: Barrow, Kirk S. S.
name: Wise, John H.
name: Norman, Michael L.
name: O'Shea, Brian W.
name: Xu, Hao
Publisher: name: arXiv
Year: 2017
Subjects: subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We present synthetic observations for the first generations of galaxies in the Universe and make predictions for future deep field observations for redshifts greater than 6. Due to the strong impact of nebular emission lines and the relatively compact scale of HII regions, high resolution cosmological simulations and a robust suite of analysis tools are required to properly simulate spectra. We created a software pipeline consisting of FSPS, Hyperion, Cloudy and our own tools to generate synthetic IR observations from a fully three-dimensional arrangement of gas, dust, and stars. Our prescription allows us to include emission lines for a complete chemical network and tackle the effect of dust extinction and scattering in the various lines of sight. We provide spectra, 2-D binned photon imagery for both HST and JWST IR filters, luminosity relationships, and emission line strengths for a large sample of high redshift galaxies in the Renaissance Simulations. Our resulting synthetic spectra show high variability between galactic halos with a strong dependence on stellar mass, metallicity, gas mass fraction, and formation history. Halos with the lowest stellar mass have the greatest variability in [OIII]/H$β$, [OIII] and CIII] while halos with higher masses are seen to show consistency in their spectra and [OIII] equivalent widths (EW) between 1Å and 10Å. Viewing angle accounted for three-fold difference in flux due to the presence of ionized gas channels in a halo. Furthermore, JWST color plots show a discernible relationship between redshift, color, and mean stellar age.
description: Version 2. 17 pages, 14 figures. Published May 15, 2017
Bayes, not Naïve: Security Bounds on Website Fingerprinting Defenses
Creators: name: Cherubin, Giovanni
Publisher: name: arXiv
Year: 2017
Subjects: subject: Cryptography and Security (cs.CR)
subject: FOS: Computer and information sciences

description: Website Fingerprinting (WF) attacks raise major concerns about users' privacy. They employ Machine Learning (ML) to allow a local passive adversary to uncover the Web browsing behavior of a user, even if she browses through an encrypted tunnel (e.g. Tor, VPN). Numerous defenses have been proposed in the past; however, it is typically difficult to have formal guarantees on their security, which is most often evaluated empirically against state-of-the-art attacks. In this paper, we present a practical method to derive security bounds for any WF defense, which depend on a chosen feature set. This result derives from reducing WF attacks to an ML classification task, where we can determine the smallest achievable error (the Bayes error); such error can be estimated in practice, and is a lower bound for a WF adversary, for any classification algorithm he may use. Our work has two main consequences: i) it allows determining the security of WF defenses, in a black-box manner, with respect to the state-of-the-art feature set and ii) it favors shifting the focus of future WF research to the identification of optimal feature sets. The generality of the approach further suggests that the method could be used to define security bounds for other ML-based attacks.
Density and current profiles in $U_q(A^{(1)}_2)$ zero range process
Creators: name: Kuniba, Atsuo
name: Mangazeev, Vladimir V.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Mathematical Physics (math-ph)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Exactly Solvable and Integrable Systems (nlin.SI)
subject: FOS: Physical sciences
subject: 81R50, 60C99

description: The stochastic $R$ matrix for $U_q(A^{(1)}_n)$ introduced recently gives rise to an integrable zero range process of $n$ classes of particles in one dimension. For $n=2$ we investigate how finitely many first class particles fixed as defects influence the grand canonical ensemble of the second class particles. By using the matrix product stationary probabilities involving infinite products of $q$-bosons, exact formulas are derived for the local density and current of the second class particles in the large volume limit.
description: 31 pages, 12 figures. Minor revision from version 1
Economics & Biology: The whole is something besides the parts – a complementary approach to a bioeconomy
Creators: name: Henkel, Joshua
Publisher: name: IERP
Year: 2022
Subjects: subject: Sustainability
subject: Culture
subject: Collapse
subject: Bio-economy
subject: 330

description: This paper examines relations between economics and biology regarding the historical background of these disciplines. Though economics is a social science its emergence has strong links to the natural sciences, especially to physics. This methodological basis seems to be mostly forgotten in mainstream economics. Since this methodology is based on the same principles of universal natural laws, it should make the branches of economics and biology compatible. Merging biology and economics could have a strong impact on finding solutions to our modern world sustainability problems and avoiding the dangers of the entropic abyss. This is only possible if mainstream economics is more open to assimilate information from outside its own field. Unequivocally, the most straightforward impact of a collaboration of these disciplines would be a biobased economy, that would tackle many problems our resource intensive and unsustainable economic system is facing at the moment.
Discrete Symmetries of Calabi-Yau Hypersurfaces in Toric Four-Folds
Creators: name: Braun, Andreas P.
name: Lukas, Andre
name: Sun, Chuang
Publisher: name: arXiv
Year: 2017
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Algebraic Geometry (math.AG)
subject: FOS: Physical sciences
subject: FOS: Mathematics

description: We analyze freely-acting discrete symmetries of Calabi-Yau three-folds defined as hypersurfaces in ambient toric four-folds. An algorithm which allows the systematic classification of such symmetries which are linearly realised on the toric ambient space is devised. This algorithm is applied to all Calabi-Yau manifolds with $h^{1,1}(X)\leq 3$ obtained by triangulation from the Kreuzer-Skarke list, a list of some $350$ manifolds. All previously known freely-acting symmetries on these manifolds are correctly reproduced and we find five manifolds with freely-acting symmetries. These include a single new example, a manifold with a $\mathbb{Z}_2\times\mathbb{Z}_2$ symmetry where only one of the $\mathbb{Z}_2$ factors was previously known. In addition, a new freely-acting $\mathbb{Z}_2$ symmetry is constructed for a manifold with $h^{1,1}(X)=6$. While our results show that there are more freely-acting symmetries within the Kreuzer-Skarke set than previously known, it appears that such symmetries are relatively rare.
description: v2: corrected typos, added Appendix with more details on examples
Topological defects in Floquet systems: Anomalous chiral modes and topological invariant
Creators: name: Bi, Ren
name: Yan, Zhongbo
name: Lu, Ling
name: Wang, Zhong
Publisher: name: arXiv
Year: 2016
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Quantum Gases (cond-mat.quant-gas)
subject: FOS: Physical sciences

description: Backscattering-immune chiral modes arise along certain line defects in three-dimensional materials. In this paper, we study Floquet chiral modes along Floquet topological defects, namely, the defects come entirely from spatial modulations of periodic driving. We define a precise topological invariant that counts the number of Floquet chiral modes, which is expressed as an integral on a five-dimensional torus parameterized by $(k_x,k_y,k_z,θ,t)$. This work demonstrates the possibility of creating chiral modes in three-dimensional bulk materials by modulated driving. We hope that it will stimulate further studies of Floquet topological defects.
description: 11 pages, 7 figures, including supplemental material. Published version
Opinion diversity and community formation in adaptive networks
Creators: name: Yu, Yi
name: Xiao, Gaoxi
name: Li, Guoqi
name: Tay, Wee Peng
name: Teoh, Hao Fatt
Publisher: name: arXiv
Year: 2017
Subjects: subject: Physics and Society (physics.soc-ph)
subject: Social and Information Networks (cs.SI)
subject: FOS: Physical sciences
subject: FOS: Computer and information sciences

description: It is interesting and of significant importance to investigate how network structures co-evolve with opinions. The existing models of such co-evolution typically lead to the final states where network nodes either reach a global consensus or break into separated communities, each of which holding its own community consensus. Such results, however, can hardly explain the richness of real-life observations that opinions are always diversified with no global or even community consensus, and people seldom, if not never, totally cut off themselves from dissenters. In this article, we show that, a simple model integrating consensus formation, link rewiring and opinion change allows complex system dynamics to emerge, driving the system into a dynamic equilibrium with co-existence of diversified opinions. Specifically, similar opinion holders may form into communities yet with no strict community consensus; and rather than being separated into disconnected communities, different communities remain to be interconnected by non-trivial proportion of inter-community links. More importantly, we show that the complex dynamics may lead to different numbers of communities at steady state with a given tolerance between different opinion holders. We construct a framework for theoretically analyzing the co-evolution process. Theoretical analysis and extensive simulation results reveal some useful insights into the complex co-evolution process, including the formation of dynamic equilibrium, the phase transition between different steady states with different numbers of communities, and the dynamics between opinion distribution and network modularity, etc.
description: 12 pages, 8 figures, Journal
Higgs-mode radiance and charge-density-wave order in 2H-NbSe$_2$
Creators: name: Grasset, Romain
name: Cea, Tommaso
name: Gallais, Yann
name: Cazayous, Maximilien
name: Sacuto, Alain
name: Cario, Laurent
name: Benfatto, Lara
name: Méasson, Marie-Aude
Publisher: name: arXiv
Year: 2017
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: Despite being usually considered two competing phenomena, charge-density-wave and superconductivity coexist in few systems, the most emblematic one being the transition metal dichalcogenide 2H-NbSe$_2$. This unusual condition is responsible for specific Raman signatures across the two phase transitions in this compound. While the appearance of a soft phonon mode is a well-established fingerprint of the charge-density-wave order, the nature of the sharp sub-gap mode emerging below the superconducting temperature is still under debate. In this work we use the external pressure as a knob to unveil the delicate interplay between the two orders, and consequently the nature of the superconducting mode. Thanks to an advanced extreme-conditions Raman technique we are able to follow the pressure evolution and the simultaneous collapse of the two intertwined charge density wave and superconducting modes. The comparison with microscopic calculations in a model system supports the Higgs-type nature of the superconducting mode and suggests that charge-density-wave and superconductivity in 2H-NbSe$_2$ involve mutual electronic degrees of freedom. These findings fill knowledge gap on the electronic mechanisms at play in transition metal dichalcogenides, a crucial step to fully exploit their properties in few-layers systems optimized for devices applications.
Proposal for VEPP-4M beam energy measurement using magnetic spectrometer with Compton calibration and photon detector
Creators: name: Kaminskiy, V. V.
name: Muchnoi, N. Yu.
name: Zhilich, V. N.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Instrumentation and Detectors (physics.ins-det)
subject: FOS: Physical sciences

description: A method for circular e$^-$/e$^+$ accelerator beam energy measurement is proposed. Coordinate of an electron (or a positron) in a focusing magnetic spectrometer built in a circular accelerator depends on its energy, two spectrometer parameters, and the circulating beam energy. The spectrometer parameters can be defined using minimum electron energies from Compton backscattering with two laser wavelengths, and an additional photon coordinate detector. The photon detector is calibrated at once at well-known beam energy. The VEPP-4M collider has appropriate equipment for the method implementation: built-in focusing magnetic spectrometer, Compton calibration system with two lasers and a photon coordinate detector. Thus, the proposed technique could be implemented with minimum efforts; tests and further upgrade are planned. The beam energy can be defined with expected uncertainty better than $10^{-4}$.
description: Proceedings of Instrumentation for Colliding Beam Physics 27 February - 3 March, 2017, Budker Institute of Nuclear Physics, Novosibirsk, Russia. 7 pages, 3 figures
Finite Size Scaling in the Kuramoto Model
Creators: name: Coletta, Tommaso
name: Delabays, Robin
name: Jacquod, Philippe
Publisher: name: arXiv
Year: 2016
Subjects: subject: Adaptation and Self-Organizing Systems (nlin.AO)
subject: FOS: Physical sciences

description: We investigate the scaling properties of the order parameter and the largest nonvanishing Lyapunov exponent for the fully locked state in the Kuramoto model with a finite number $N$ of oscillators. We show that, for any finite value of $N$, both quantities scale as $(K-K_L)^{1/2}$ with the coupling strength $K$ sufficiently close to the locking threshold $K_L$. We confirm numerically these predictions for oscillator frequencies evenly spaced in the interval $[-1, 1]$ and additionally find that the coupling range $δK$ over which this scaling is valid shrinks like $δK \sim N^{-α}$ with $α\approx1.5$ as $N \rightarrow \infty$. Away from this interval, the order parameter exhibits the infinite-$N$ behavior $r-r_L \sim (K-K_L)^{2/3}$ proposed by Pazó [Phys. Rev. E 72, 046211 (2005)]. We argue that the crossover between the two behaviors occurs because at the locking threshold, the upper bound of the continuous part of the spectrum of the fully locked state approaches zero as $N$ increases. Our results clarify the convergence to the $N \rightarrow \infty$ limit in the Kuramoto model.
description: 7 pages, 5 figures
DecTrain: Deciding When to Train a Monocular Depth DNN Online
Creators: name: Fu, Zih-Sing
name: Sudhakar, Soumya
name: Karaman, Sertac
name: Sze, Vivienne
Publisher: name: arXiv
Year: 2024
Subjects: subject: Machine Learning (cs.LG)
subject: Robotics (cs.RO)
subject: FOS: Computer and information sciences

description: Deep neural networks (DNNs) can deteriorate in accuracy when deployment data differs from training data. While performing online training at all timesteps can improve accuracy, it is computationally expensive. We propose DecTrain, a new algorithm that decides when to train a monocular depth DNN online using self-supervision with low overhead. To make the decision at each timestep, DecTrain compares the cost of training with the predicted accuracy gain. We evaluate DecTrain on out-of-distribution data, and find DecTrain maintains accuracy compared to online training at all timesteps, while training only 44% of the time on average. We also compare the recovery of a low inference cost DNN using DecTrain and a more generalizable high inference cost DNN on various sequences. DecTrain recovers the majority (97%) of the accuracy gain of online training at all timesteps while reducing computation compared to the high inference cost DNN which recovers only 66%. With an even smaller DNN, we achieve 89% recovery while reducing computation by 56%. DecTrain enables low-cost online training for a smaller DNN to have competitive accuracy with a larger, more generalizable DNN at a lower overall computational cost.
description: 8 pages
Quantum Nonlinear Optics without Photons
Creators: name: Stassi, Roberto
name: Macrì, Vincenzo
name: Kockum, Anton Frisk
name: Di Stefano, Omar
name: Miranowicz, Adam
name: Savasta, Salvatore
name: Nori, Franco
Publisher: name: arXiv
Year: 2017
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Spontaneous parametric down-conversion is a well-known process in quantum nonlinear optics in which a photon incident on a nonlinear crystal spontaneously splits into two photons. Here we propose an analogous physical process where one excited atom directly transfers its excitation to a pair of spatially-separated atoms with probability approaching one. The interaction is mediated by the exchange of virtual rather than real photons. This nonlinear atomic process is coherent and reversible, so the pair of excited atoms can transfer the excitation back to the first one: the atomic analogue of sum-frequency generation of light. The parameters used to investigate this process correspond to experimentally-demonstrated values in ultrastrong circuit quantum electrodynamics. This approach can be extended to realize other nonlinear inter-atomic processes, such as four-atom mixing, and is an attractive architecture for the realization of quantum devices on a chip. We show that four-qubit mixing can efficiently implement quantum repetition codes and, thus, can be used for error-correction codes.
Towards a unified lattice kinetic scheme for relativistic hydrodynamics
Creators: name: Gabbana, A.
name: Mendoza, M.
name: Succi, S.
name: Tripiccione, R.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Computational Physics (physics.comp-ph)
subject: FOS: Physical sciences

description: We present a systematic derivation of relativistic lattice kinetic equations for finite-mass particles, reaching close to the zero-mass ultra-relativistic regime treated in the previous literature. Starting from an expansion of the Maxwell-Juettner distribution on orthogonal polynomials, we perform a Gauss-type quadrature procedure and discretize the relativistic Boltzmann equation on space-filling Cartesian lattices. The model is validated through numerical comparison with standard benchmark tests and solvers in relativistic fluid dynamics such as Boltzmann approach multiparton scattering (BAMPS) and previous relativistic lattice Boltzmann models. This work provides a significant step towards the formulation of a unified relativistic lattice kinetic scheme, covering both massive and near-massless particles regimes.
Radiative Decays of the Higgs Boson to a Pair of Fermions
Creators: name: Han, Tao
name: Wang, Xing
Publisher: name: arXiv
Year: 2017
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We revisit the radiative decays of the Higgs boson to a fermion pair $h\rightarrow f\bar{f}γ$ where $f$ denotes a fermion in the Standard Model (SM). We include the chirality-flipping diagrams via the Yukawa couplings at the order $\mathcal{O}(y_f^2 α)$, the chirality-conserving contributions via the top-quark loops of the order $\mathcal{O}(y_t^2 α^3)$, and the electroweak loops at the order $\mathcal{O}(α^4)$. The QED correction is about $Q_f^2\times {\cal O}(1\%)$ and contributes to the running of fermion masses at a similar level, which should be taken into account for future precision Higgs physics. The chirality-conserving electroweak-loop processes are interesting from the observational point of view. First, the branching fraction of the radiative decay $h \to μ^+μ^- γ$ is about a half of that of $h \to μ^+μ^-$, and that of $h \to e^+ e^- γ$ is more than four orders of magnitude larger than that of $h \to e^+ e^-$, both of which reach about $10^{-4}$. The branching fraction of $h \to τ^+τ^- γ$ is of the order $10^{-3}$. All the leptonic radiative decays are potentially observable at the LHC Run 2 or the HL-LHC. The kinematic distributions for the photon energy or the fermion pair invariant mass provide non-ambiguous discrimination for the underlying mechanisms of the Higgs radiative decay. We also study the process $h \to c\bar c γ$ and evaluate the observability at the LHC. We find it comparable to the other related studies and better than the $h \to J/ψ γ$ channel in constraining the charm-Yukawa coupling.
description: 23 pages, 6 figures, 6 tables; Minor corrections, references updated, version published in JHEP
Equation of state of the SU($3$) Yang-Mills theory: a precise determination from a moving frame
Creators: name: Giusti, Leonardo
name: Pepe, Michele
Publisher: name: arXiv
Year: 2016
Subjects: subject: High Energy Physics - Lattice (hep-lat)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: The equation of state of the SU($3$) Yang-Mills theory is determined in the deconfined phase with a precision of about 0.5%. The calculation is carried out by numerical simulations of lattice gauge theory with shifted boundary conditions in the time direction. At each given temperature, up to $230\, T_c$ with $T_c$ being the critical temperature, the entropy density is computed at several lattice spacings so to be able to extrapolate the results to the continuum limit with confidence. Taken at face value, above a few $T_c$ the results exhibit a striking linear behaviour in $\ln(T/T_c)^{-1}$ over almost 2 orders of magnitude. Within errors, data point straight to the Stefan-Boltzmann value but with a slope grossly different from the leading-order perturbative prediction. The pressure is determined by integrating the entropy in the temperature, while the energy density is extracted from $T s=(ε+ p )$. The continuum values of the potentials are well represented by Padé interpolating formulas, which also connect them well to the Stefan-Boltzmann values in the infinite temperature limit. The pressure, the energy and the entropy densities are compared with results in the literature. The discrepancy among previous computations near $T_c$ is analyzed and resolved thanks to the high precision achieved.
description: 7 pages, 3 figures. A few sentences and one reference added
Effective kinetic description of the expanding overoccupied Glasma
Creators: name: Tanji, Naoto
name: Venugopalan, Raju
Publisher: name: arXiv
Year: 2017
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: We report on a numerical study of the Boltzmann equation including $2\leftrightarrow 2$ scatterings of gluons and quarks in an overoccupied Glasma undergoing longitudinal expansion. We find that when a cascade of gluon number to the infrared occurs, corresponding to an infrared enhancement analogous to a transient Bose-Einstein condensate, gluon distributions qualitatively reproduce the results of classical-statistical simulations for the expanding Glasma. These include key features of the distributions that are not anticipated in the "bottom-up" thermalization scenario. We also find that quark distributions, like those of gluons, satisfy self-similar scaling distributions in the overoccupied Glasma. We discuss the implications of these results for a deeper understanding of the self-similarity and universality of parton distributions in the Glasma.
description: 34 pages, 21 figures; version accepted in PRD
More on products of Baire spaces
Creators: name: Li, Rui
name: Zsilinszky, László
Publisher: name: arXiv
Year: 2017
Subjects: subject: General Topology (math.GN)
subject: FOS: Mathematics
subject: 91A44, 54E52, 54B10

description: New results on the Baire product problem are presented. It is shown that an arbitrary product of almost locally ccc Baire spaces is Baire; moreover, the product of a Baire space and a 1st countable space which is $β$-unfavorable in the strong Choquet game is Baire.
Quark-Nuclear Hybrid EoS with Excluded Volume Effects
Creators: name: Kaltenborn, Mark Alexander Randolph
name: Bastian, Niels-Uwe Friedrich
name: Blaschke, David Bernhard
Publisher: name: arXiv
Year: 2017
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: A two-phase description of the quark-nuclear matter hybrid equation of state that takes into account the effect of excluded volume in both the hadronic and the quark matter phases is introduced. The nuclear phase manifests a reduction of the available volume as density increases, leading to a stiffening of the matter. The quark matter phase displays a reduction of the effective string tension in the confining density functional from available volume contributions. The nuclear equation of state is based upon the relativistic density functional model DD2 with excluded volume. The quark matter is based upon a mean-field modification to the free fermi gas and will be discussed in greater detail. The interactions are decomposed into mean scalar and vector components. The scalar interaction is motivated by a string potential between quarks, whereas the vector interaction potential is motivated by higher order interactions of quarks leading to an increased stiffening at high densities. As an application, we consider matter under compact star constraints of electric neutrality and $β$-equilibrium. We obtain mass-radius relations for hybrid stars that form a third family, disconnected from the purely hadronic star branch, and fulfill the $2M_\odot$ constraint.
description: 12 pages, 18 figures, two figures added and others remastered, text and references added, typos removed
The curiously warped mean plane of the Kuiper belt
Creators: name: Volk, Kathryn
name: Malhotra, Renu
Publisher: name: arXiv
Year: 2017
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: We measured the mean plane of the Kuiper belt as a function of semi-major axis. For the classical Kuiper belt as a whole (the non-resonant objects in the semi-major axis range 42--48~au), we find a mean plane of inclination $i_m=1.8^{\circ}$$^{+0.7^{\circ}}_{-0.4^{\circ}}$ and longitude of ascending node $Ω_m=77^{\circ}$$^{+18^{\circ}}_{-14^{\circ}}$ (in the J2000 ecliptic-equinox coordinate system), in accord with theoretical expectations of the secular effects of the known planets. With finer semi-major axis bins, we detect a statistically significant warp in the mean plane near semi-major axes 40--42~au. Linear secular theory predicts a warp near this location due to the $ν_{18}$ nodal secular resonance, however the measured mean plane for the 40.3-42~au semi-major axis bin (just outside the $ν_{18}$) is inclined $\sim13^{\circ}$ to the predicted plane, a nearly 3-$σ$ discrepancy. For the more distant Kuiper belt objects of semi-major axes in the range 50--80~au, the expected mean plane is close to the invariable plane of the solar system, but the measured mean plane deviates greatly from this: it has inclination $i_m=9.1^{\circ}$$^{+6.6^{\circ}}_{-3.8^{\circ}}$ and longitude of ascending node $Ω_m=227^{\circ}$$^{+18^{\circ}}_{-44^{\circ}}$. We estimate this deviation from the expected mean plane to be statistically significant at the $\sim97-99\%$ confidence level. We discuss several possible explanations for this deviation, including the possibility that a relatively close-in ($a\lesssim100$~au), unseen small planetary-mass object in the outer solar system is responsible for the warping.
description: This version corrects an error in Figure 7 and typographical errors in some equations in Appendix D (changes accepted as an erratum in AJ)
Kinetic inhibition of MHD-shocks in the vicinity of a parallel magnetic field
Creators: name: Bret, Antoine
name: Pe'er, Asaf
name: Sironi, Lorenzo
name: Sadowski, Aleksander
name: Narayan, Ramesh
Publisher: name: arXiv
Year: 2017
Subjects: subject: Plasma Physics (physics.plasm-ph)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: Space Physics (physics.space-ph)
subject: FOS: Physical sciences

description: According to magnetohydrodynamics (MHD), the encounter of two collisional magnetized plasmas at high velocity gives rise to shock waves. Investigations conducted so far have found that the same conclusion still holds in the case of collisionless plasmas. For the case of a flow-aligned field, MHD stipulates that the field and the fluid are disconnected, so that the shock produced is independent of the field. We present a violation of this MHD prediction when considering the encounter of two cold pair plasmas along a flow-aligned magnetic field. As the guiding magnetic field grows, isotropization is progressively suppressed, resulting in a strong influence of the field on the resulting structure. A micro-physics analysis allows to understand the mechanisms at work. Particle-in-cell simulations also support our conclusions and show that the results are not restricted to a strictly parallel field.
description: To appear in Journal of Plasma Physics