cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
The n-term Approximation of Periodic Generalized Lévy Processes
Creators: name: Fageot, Julien
name: Unser, Michael
name: Ward, John Paul
Publisher: name: arXiv
Year: 2017
Subjects: subject: Probability (math.PR)
subject: FOS: Mathematics
subject: 60G20, 41A25

description: In this paper, we study the compressibility of random processes and fields, called generalized Lévy processes, that are solutions of stochastic differential equations driven by $d$-dimensional periodic Lévy white noises. Our results are based on the estimation of the Besov regularity of Lévy white noises and generalized Lévy processes. We show in particular that non-Gaussian generalized Lévy processes are more compressible in a wavelet basis than the corresponding Gaussian processes, in the sense that their $n$-term approximation error decays faster. We quantify this compressibility in terms of the Blumenthal-Getoor index of the underlying Lévy white noise.
description: 23 pages
Hydrodynamic charge and heat transport on inhomogeneous curved spaces
Creators: name: Scopelliti, Vincenzo
name: Schalm, Koenraad
name: Lucas, Andrew
Publisher: name: arXiv
Year: 2017
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We develop the theory of hydrodynamic charge and heat transport in strongly interacting quasi-relativistic systems on manifolds with inhomogeneous spatial curvature. In solid-state physics, this is analogous to strain disorder in the underlying lattice. In the hydrodynamic limit, we find that the thermal and electrical conductivities are dominated by viscous effects, and that the thermal conductivity is most sensitive to this disorder. We compare the effects of inhomogeneity in the spatial metric to inhomogeneity in the chemical potential, and discuss the extent to which our hydrodynamic theory is relevant for experimentally realizable condensed matter systems, including suspended graphene at the Dirac point.
description: 15+8 pages, 4+1 figures; v2: added references, published version
Primordial black holes from supersymmetry in the early universe
Creators: name: Cotner, Eric
name: Kusenko, Alexander
Publisher: name: arXiv
Year: 2016
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: Supersymmetric extensions of the standard model generically predict that in the early universe a scalar condensate can form and fragment into Q-balls before decaying. If the Q-balls dominate the energy density for some period of time, the relatively large fluctuations in their number density can lead to formation of primordial black holes (PBH). Other scalar fields, unrelated to supersymmetry, can play a similar role. For a general charged scalar field, this robust mechanism can generate black holes over the entire mass range allowed by observational constraints, with a sufficient abundance to account for all dark matter in some parameter ranges. In the case of supersymmetry the mass range is limited from above by $10^{23}$g. We also comment on the role that topological defects can play for PBH formation in a similar fashion.
description: 5 pages, 3 figures
Weber Revisited: The Protestant Ethic and the Spirit of Nationalism
Creators: name: Kersting, Felix
name: Wohnsiedler, Iris
name: Wolf, Nikolaus
Publisher: name: Humboldt-Universität zu Berlin
Year: 2020
Subjects: subject: 943 Deutschland und benachbarte mitteleuropäische Länder

description: We revisit Max Weber’s hypothesis on the role of Protestantism for economic development. We show that nationalism is crucial to both, the interpretation of Weber’s Protestant Ethic and empirical tests thereof. For late nineteenth-century century Prussia we reject Weber’s suggestion that Protestantism mattered due to an “ascetic compulsion to save.” Moreover, we find that income levels, savings, and literacy rates differed between Germans and Poles, not between Protestants and Catholics, using pooled OLS and IV regressions. We suggest that this result is due to anti-Polish discrimination.
Density Matrix Modeling of Quantum Cascade Lasers without an Artificially Localized Basis: A Generalized Scattering Approach
Creators: name: Pan, Andrew
name: Burnett, Benjamin A.
name: Chui, Chi On
name: Williams, Benjamin S.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: We derive a density matrix (DM) theory for quantum cascade lasers (QCLs) that describes the influence of scattering on coherences through a generalized scattering superoperator. The theory enables quantitative modeling of QCLs, including localization and tunneling effects, using the well-defined energy eigenstates rather than the ad hoc localized basis states required by most previous DM models. Our microscopic approach to scattering also eliminates the need for phenomenological transition or dephasing rates. We discuss the physical interpretation and numerical implementation of the theory, presenting sets of both energy-resolved and thermally averaged equations which can be used for detailed or compact device modeling. We illustrate the theory's applications by simulating a high performance resonant-phonon terahertz (THz) QCL design which cannot be easily or accurately modeled using conventional DM methods. We show that the theory's inclusion of coherences is crucial for describing localization and tunneling effects consistent with experiment.
description: 20 pages, 9 figures, final version in Physical Review B
The reference system and not completely positive open quantum dynamics
Creators: name: Joseph, Linta
name: Shaji, Anil
Publisher: name: arXiv
Year: 2017
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Open quantum dynamics in a tripartite scenario including a system, its environment and a passive reference is shown to resolve several open questions regarding not completely positive (NCP) dynamical maps as valid descriptions of open quantum evolution. The steering states of the system and the environment with respect to the reference, reduced down to a dense, compact set of states of the system alone, provides a well defined domain of action for a bonafide dynamical map describing the open evolution of the system. The map is not restricted to being completely positive (CP) but it preserves the positivity of all states in its domain. NCP open dynamics corresponding to different initial configurations of the tripartite system are explored.
description: 9 pages, 4 figures
Paths to equilibrium in non-conformal collisions
Creators: name: Attems, Maximilian
name: Casalderrey-Solana, Jorge
name: Mateos, David
name: Santos-Oliván, Daniel
name: Sopuerta, Carlos F.
name: Triana, Miquel
name: Zilhão, Miguel
Publisher: name: arXiv
Year: 2017
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: We extend our previous analysis of holographic heavy ion collisions in non-conformal theories. We provide a detailed description of our numerical code. We study collisions at different energies in gauge theories with different degrees of non-conformality. We compare four relaxation times: the hydrodynamization time (when hydrodynamics becomes applicable), the EoSization time (when the average pressure approaches its equilibrium value), the isotropization time (when the longitudinal and transverse pressures approach each other) and the condensate relaxation time (when the expectation value of a scalar operator approaches its equilibrium value). We find that these processes can occur in several different orderings. In particular, the condensate can remain far from equilibrium even long after the plasma has hydrodynamized and EoSized. We also explore the rapidity distribution of the energy density at hydrodynamization. This is far from boost-invariant and its width decreases as the non-conformality increases. Nevertheless, the velocity field at hydrodynamization is almost exactly boost-invariant regardless of the non-conformality. This result may be used to constrain the initialization of hydrodynamic fields in heavy ion collisions.
description: 45 pages, 17 figures. Expanded some sections. Matches published version in JHEP
A robust mass estimator for dark matter subhalo perturbations in strong gravitational lenses
Creators: name: Minor, Quinn E.
name: Kaplinghat, Manoj
name: Li, Nan
Publisher: name: arXiv
Year: 2016
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: A few dark matter substructures have recently been detected in strong gravitational lenses though their perturbations of highly magnified images. We derive a characteristic scale for lensing perturbations and show that this is significantly larger than the perturber's Einstein radius. We show that the perturber's projected mass enclosed within this radius, scaled by the log-slope of the host galaxy's density profile, can be robustly inferred even if the inferred density profile and tidal radius of the perturber are biased. We demonstrate the validity of our analytic derivation by using several gravitational lens simulations where the tidal radii and the inner log-slopes of the density profile of the perturbing subhalo are allowed to vary. By modeling these simulated data we find that our mass estimator, which we call the effective subhalo lensing mass, is accurate to within about 10\% or smaller in each case, whereas the inferred total subhalo mass can potentially be biased by nearly an order of magnitude. We therefore recommend that the effective subhalo lensing mass be reported in future lensing reconstructions, as this will allow for a more accurate comparison with the results of dark matter simulations.
description: 21 pages, 8 figures, 2 appendices, accepted for publication in ApJ
Supplementary document for High-resolution multi-z confocal microscopy with a diffractive optical element - 6433100.pdf
Creators: name: Zhao, Bingying
name: Koyama, Minoru
name: Mertz, Jerome
Publisher: name: Optica Publishing Group
Year: 2023
Subjects: subject: 99902 Engineering Instrumentation
subject: FOS: Other engineering and technologies
subject: Biological Engineering
subject: Cardiology
subject: Neuroscience
subject: 60801 Animal Behaviour
subject: FOS: Biological sciences
subject: 60805 Animal Neurobiology
subject: 60807 Animal Structure and Function

description: Supplemental document
Clustered Hyperbolic Categories
Creators: name: Saleh, Ibrahim
Publisher: name: arXiv
Year: 2017
Subjects: subject: Representation Theory (math.RT)
subject: FOS: Mathematics

description: We introduce a class of categories, called \emph{clustered hyperbolic categories}, which are generated by equivalent categories of representations of some Weyl cluster algebras. Every preseed $p$ gives rise to a \emph{categorical preseed} $\mathcal{P}$ which generates a clustered hyperbolic category through \emph{categorical mutations}. A "categorification" of Weyl cluster algebra is introduced in the sense of defining a map $\mathbf{F}_{p}$ from the clustered hyperbolic category $\mathfrak{C}(\mathcal{P})$ to the Weyl cluster algebra $\mathcal{H}(p)$ where image of $\mathbf{F}_{p}$ generates $\mathcal{H}(p)$.
Regularization with Numerical Extrapolation for Finite and UV-Divergent Multi-loop Integrals
Creators: name: de Doncker, E.
name: Yuasa, F.
name: Kato, K.
name: Ishikawa, T.
name: Kapenga, J.
name: Olagbemi, O.
Publisher: name: arXiv
Year: 2017
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We give numerical integration results for Feynman loop diagrams such as those covered by Laporta [1] and by Baikov and Chetyrkin [2], and which may give rise to loop integrals with UV singularities. We explore automatic adaptive integration using multivariate techniques from the PARINT package for multivariate integration, as well as iterated in- tegration with programs from the QUADPACK package, and a trapezoidal method based on a double exponential trans- formation. PARINT is layered over MPI (Message Passing Interface), and incorporates advanced parallel/distributed techniques including load balancing among processes that may be distributed over a cluster or a network/grid of nodes. Results are included for 2-loop vertex and box diagrams and for sets of 2-, 3- and 4-loop self-energy diagrams with or without UV terms. Numerical regularization of integrals with singular terms is achieved by linear and non-linear extrapolation methods.
description: replaced by published version
Solvable Hydrodynamics of Quantum Integrable Systems
Creators: name: Bulchandani, Vir B.
name: Vasseur, Romain
name: Karrasch, Christoph
name: Moore, Joel E.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: The conventional theory of hydrodynamics describes the evolution in time of chaotic many-particle systems from local to global equilibrium. In a quantum integrable system, local equilibrium is characterized by a local generalized Gibbs ensemble or equivalently a local distribution of pseudo-momenta. We study time evolution from local equilibria in such models by solving a certain kinetic equation, the "Bethe-Boltzmann" equation satisfied by the local pseudo-momentum density. Explicit comparison with density matrix renormalization group time evolution of a thermal expansion in the XXZ model shows that hydrodynamical predictions from smooth initial conditions can be remarkably accurate, even for small system sizes. Solutions are also obtained in the Lieb-Liniger model for free expansion into vacuum and collisions between clouds of particles, which model experiments on ultracold one-dimensional Bose gases.
description: 6+5 pages, published version
Economic Accelerator with Memory: Discrete Time Approach
Creators: name: Tarasova, Valentina V.
name: Tarasov, Vasily E.
Publisher: name: arXiv
Year: 2016
Subjects: subject: General Economics (econ.GN)
subject: Mathematical Finance (q-fin.MF)
subject: FOS: Economics and business
subject: 26A33, 34A08, 39A70, 93C55, 37N40

description: Accelerators with power-law memory are proposed in the framework of the discrete time approach. To describe discrete accelerators we use the capital stock adjustment principle, which has been suggested by Matthews.The suggested discrete accelerators with memory describe the economic processes with the power-law memory and the periodic sharp splashes (kicks). In continuous time approach the memory is described by fractional-order differential equations. In discrete time approach the accelerators with memory are described by discrete maps with memory, which are derived from the fractional-order differential equation without approximations. In order to derive these maps we use the equivalence of fractional-order differential equations and the Volterra integral equations.
description: 8 pages, PDF
Linear Stability Analysis of a Levitated Nanomagnet in a Static Magnetic Field: Quantum Spin Stabilized Magnetic Levitation
Creators: name: Rusconi, Cosimo C.
name: Pöchhacker, Vera
name: Cirac, J. Ignacio
name: Romero-Isart, Oriol
Publisher: name: arXiv
Year: 2017
Subjects: subject: Quantum Physics (quant-ph)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: We theoretically study the levitation of a single magnetic domain nanosphere in an external static magnetic field. We show that apart from the stability provided by the mechanical rotation of the nanomagnet (as in the classical Levitron), the quantum spin origin of its magnetization provides two additional mechanisms to stably levitate the system. Despite of the Earnshaw theorem, such stable phases are present even in the absence of mechanical rotation. For large magnetic fields, the Larmor precession of the quantum magnetic moment stabilizes the system in full analogy with magnetic trapping of a neutral atom. For low magnetic fields, the magnetic anisotropy stabilizes the system via the Einstein-de Haas effect. These results are obtained with a linear stability analysis of a single magnetic domain rigid nanosphere with uniaxial anisotropy in a Ioffe-Pritchard magnetic field.
description: Published version. 10 pages, 4 figures, 3 tables
Cosmic ray spectrum in the local Galaxy
Creators: name: Neronov, Andrii
name: Malyshev, Denys
name: Semikoz, Dmitri V.
Publisher: name: arXiv
Year: 2017
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: We study the spectral properties of the cosmic-ray spectrum in the interstellar medium within 1 kpc distance from the Sun. We used eight-year exposure data of molecular clouds of the Gould Belt obtained with the Fermi/LAT telescope to precisely measure the cosmic-ray spectrum at different locations in the local Galaxy. We compared this measurement with the direct measurements of the cosmic-ray flux in and around the solar system obtained by Voyager and AMS-02 or PAMELA. We find that the average cosmic-ray spectrum in the local Galaxy in the 1-100 GeV range is well described by a broken power-law in rigidity with a low-energy slope of $2.33^{+0.06}_{-0.08}$ and a break at $18^{+7}_{-4}$ GV, with a slope change by $0.59\pm 0.11$. This result is consistent with an earlier analysis of the gamma-ray signal from the Gould Belt clouds based on a shorter exposure of Fermi/LAT and with a different event selection. The break at 10-20 GV is also consistent with the combined Voyager + AMS-02 measurements in/around the solar system. The slope of the spectrum below the break agrees with the slope of the average cosmic-ray spectrum in the inner part of the disk of the Milky Way that was previously derived from the Fermi/LAT gamma-ray data. We conjecture that it is this slope of 2.33 and not the locally measured softer slope of 2.7-2.8 that is determined by the balance between a steady-state injection of cosmic rays with a power-law slope of 2-2.1 that is due to Fermi acceleration and the energy-dependent propagation of cosmic-ray particles through the turbulent interstellar magnetic field with a Kolmogorov turbulence spectrum. The approximation of a continuous-in-time injection of cosmic rays at a constant rate breaks down, which causes the softening of the spectrum at higher energies.
description: to match the accepted version
Light vector correlator in medium: Wilson coefficients up to dimension 6 operators
Creators: name: Kim, HyungJoo
name: Gubler, Philipp
name: Lee, Su Houng
Publisher: name: arXiv
Year: 2017
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Experiment (hep-ex)
subject: High Energy Physics - Lattice (hep-lat)
subject: Nuclear Experiment (nucl-ex)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: As an improvement of the QCD sum rule method to study modifications of light vector mesons in nuclear matter and/or at finite temperature, we calculate the Wilson coefficients of all independent gluonic non-scalar operators up to dimension 6 in the operator product expansion (OPE) of the vector channel for light quarks. To obtain the gluon part of the light quark OPE from the heavy quark one, we also compute the heavy quark expansion of the relevant quark condensates. Together with the results for the quark operators that are already available in the literature, this completes the OPE of the vector channel in a hot or dense medium for operators up to dimension 6.
description: 6 pages, no figure
Evolution of favoritism and group fairness in a co-evolving three-person ultimatum game
Creators: name: Takesue, Hirofumi
name: Ozawa, Akira
name: Morikawa, So
Publisher: name: arXiv
Year: 2016
Subjects: subject: Physics and Society (physics.soc-ph)
subject: FOS: Physical sciences

description: The evolution of fairness in dyadic relationships has been studied using ultimatum games. However, human fairness is not limited to two-person situations and universal egalitarianism among group members is widely observed. In this study, we investigated the evolution of favoritism and group fairness in a three-person ultimatum game (TUG) under a co-evolutionary framework with both strategy updating and partner switching dynamics. In the TUG, one proposer makes an offer to two responders and the proposal is accepted at the group level if at least one individual responder accepts the offer. Investigating fairness beyond dyadic relationships allows the possibility of favoritism because the proposer can secure acceptance at the group level by discriminating in favor of one responder. Our simulation showed that the proposer favors one responder with a similar type when the frequency of partner switching is low. In contrast, group fairness is observed when the frequency of partner switching is high. The correlation between strategy and neighborhood size suggested that partner switching influences the strategy through the proposer's offer rather than through the responder's acceptance threshold. In addition, the average degree negatively impacts the emergence of fairness unless the frequency of partner switching is high. Furthermore, a higher frequency of partner switching can support the evolution of fairness when the maximum number of games in one time step is restricted to smaller values.
description: 7pages, 6figures; Interpretations of Fig.2 and Fig.4 are revised based on referee comments. Fig.5 was added. Accepted for publication in EPL (Europhysics Letters)
Aspherical neighborhoods on arithmetic surfaces: the local case
Creators: name: Hübner, Katharina
Publisher: name: arXiv
Year: 2017
Subjects: subject: Algebraic Geometry (math.AG)
subject: FOS: Mathematics
subject: 14G40 (Primary) 11G99, 14B15 (Secondary)

description: On arithmetic surfaces over local rings of integers we examine whether any geometric point has a basis of étale neighborhoods whose $\mathfrak{c}$-completed étale homotopy types are of type $K(π,1)$ for a given full class~$\mathfrak{c}$ of finite groups.
Chimera states in multi-strain epidemic models with temporary immunity
Creators: name: Bauer, Larissa
name: Bassett, Jason
name: Hövel, Philipp
name: Kyrychko, Yuliya N.
name: Blyuss, Konstantin B.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Adaptation and Self-Organizing Systems (nlin.AO)
subject: Chaotic Dynamics (nlin.CD)
subject: FOS: Physical sciences
subject: 37F99

description: We investigate a time-delayed epidemic model for multi-strain diseases with temporary immunity. In the absence of cross-immunity between strains, dynamics of each individual strain exhibits emergence and anni- hilation of limit cycles due to a Hopf bifurcation of the endemic equilibrium, and a saddle-node bifurcation of limit cycles depending on the time delay associated with duration of temporary immunity. Effects of all-to-all and non-local coupling topologies are systematically investigated by means of numerical simulations, and they suggest that cross-immunity is able to induce a diverse range of complex dynamical behaviors and synchro- nization patterns, including discrete traveling waves, solitary states, and amplitude chimeras. Interestingly, chimera states are observed for narrower cross-immunity kernels, which can have profound implications for understanding the dynamics of multi-strain diseases.
description: 9 pages, 13 figures
Noninteger-spin magnonic excitations in untextured magnets
Creators: name: Kamra, Akashdeep
name: Agrawal, Utkarsh
name: Belzig, Wolfgang
Publisher: name: arXiv
Year: 2016
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: Interactions are responsible for intriguing physics, e.g. emergence of exotic ground states and excitations, in a wide range of systems. Here we theoretically demonstrate that dipole-dipole interaction leads to bosonic eigen-excitations with average spin ranging from zero to above $\hbar$ in magnets with uniformly magnetized ground states. These exotic excitations can be interpreted as quantum coherent conglomerates of spin $\hbar$ magnons, the eigen-excitations when the dipolar interactions are disregarded. We further find that the eigenmodes in an easy-axis antiferromagnet are spin-zero quasiparticles instead of the widely believed spin $\pm \hbar$ magnons. The latter re-emerge when the symmetry is broken by a sufficiently large applied magnetic field. The average spin greater than $\hbar$ is accompanied by vacuum fluctuations and may be considered to be a weak form of frustration.
description: 5 pages, 3 figures, Supplementary material
Four dimensional ambitwistor strings and form factors of local and Wilson line operators
Creators: name: Bork, L. V.
name: Onishchenko, A. I.
Publisher: name: arXiv
Year: 2017
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We consider the description of form factors of local and Wilson line operators (reggeon amplitudes) in N=4 SYM within the framework of four dimensional ambitwistor string theory. We present the explicit expressions for string composite operators corresponding to stress-tensor operator supermultiplet and Wilson line operator insertion. It is shown, that corresponding tree-level string correlation functions correctly reproduce previously obtained Grassmannian integral representations. As by product we derive four dimensional tree-level scattering equations representations for the mentioned form factors and formulate a simple gluing procedure used to relate operator form factors with on-shell amplitudes.
description: 46 pages, 3 figures; v3: multiple changes in the text, typos corrected, references added
Successive Convexification of Non-Convex Optimal Control Problems with State Constraints
Creators: name: Mao, Yuanqi
name: Dueri, Daniel
name: Szmuk, Michael
name: Açıkmeşe, Behçet
Publisher: name: arXiv
Year: 2017
Subjects: subject: Optimization and Control (math.OC)
subject: FOS: Mathematics

description: This paper presents a Successive Convexification ($ \texttt{SCvx} $) algorithm to solve a class of non-convex optimal control problems with certain types of state constraints. Sources of non-convexity may include nonlinear dynamics and non-convex state/control constraints. To tackle the challenge posed by non-convexity, first we utilize exact penalty function to handle the nonlinear dynamics. Then the proposed algorithm successively convexifies the problem via a $ \textit{project-and-linearize} $ procedure. Thus a finite dimensional convex programming subproblem is solved at each succession, which can be done efficiently with fast Interior Point Method (IPM) solvers. Global convergence to a local optimum is demonstrated with certain convexity assumptions, which are satisfied in a broad range of optimal control problems. The proposed algorithm is particularly suitable for solving trajectory planning problems with collision avoidance constraints. Through numerical simulations, we demonstrate that the algorithm converges reliably after only a few successions. Thus with powerful IPM based custom solvers, the algorithm can be implemented onboard for real-time autonomous control applications.
description: This is the published version in Proceedings of 20th IFAC World Congress, Toulouse, France, July 2017. Online access: https://www.sciencedirect.com/science/article/pii/S2405896317312405
Extending applicability of bimetric theory: chameleon bigravity
Creators: name: De Felice, Antonio
name: Mukohyama, Shinji
name: Uzan, Jean-Philippe
Publisher: name: arXiv
Year: 2017
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: This article extends bimetric formulations of massive gravity to make the mass of the graviton to depend on its environment. This minimal extension offers a novel way to reconcile massive gravity with local tests of general relativity without invoking the Vainshtein mechanism. On cosmological scales, it is argued that the model is stable and that it circumvents the Higuchi bound, hence relaxing the constraints on the parameter space. Moreover, with this extension the strong coupling scale is also environmentally dependent in such a way that it is kept sufficiently higher than the expansion rate all the way up to the very early universe, while the present graviton mass is low enough to be phenomenologically interesting. In this sense the extended bigravity theory serves as a partial UV completion of the standard bigravity theory. This extension is very generic and robust and a simple specific example is described.
description: 6 pages, uses RevTeX4.1
Skills4EOSC induction: A quick reference guide for busy communicators
Creators: name: Tanlongo, Federica
Publisher: name: Zenodo
Year: 2022
Subjects: skills4EOSC
competences
open science
communication
EOSC

description: This presentation provides a quick reference guide for communcators involved in the Skills4EOSC project, or for people occasionally contribution to the project communication and dissemination. The presentation is part of an induction webinar format intended to onboard the project staff and engage with relevant people in the organisation (e.g. their social media managers or press offices), providing basic information about the project context, vision, and activities.
SU(3) Landau-Zener interferometry with a transverse periodic drive
Creators: name: Kenmoe, M. B.
name: Tchapda, A. B.
name: Fai, L. C.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Quantum Physics (quant-ph)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: Quantum triangles can work as interferometers. Depending on their geometric size and interactions between paths, "beats" {\it and/or} "steps" patterns are observed. We show that when inter-level distances between level positions in quantum triangles periodically change with time, formation of beats {\it and/or} steps no longer depends only on the geometric size of the triangles but also on the characteristic frequency of the transverse signal. For large-size triangles, we observe the coexistence of beats {\it and} steps when the frequency of the signal matches that of non-adiabatic oscillations and for large frequencies, a maximum of four steps instead of two as in the case with constant interactions is observed. Small-size triangles also revealed counter-intuitive interesting dynamics for large frequencies of the field: unexpected two-step patterns are observed. When the frequency is large and tuned such that it matches the uniaxial anisotropy, three-step patterns are observed. We have equally observed that when the transverse signal possesses a static part, steps maximize to six. These effects are semi-classically explained in terms of Fresnel integrals and quantum mechanically in terms of quantized fields with a photon-induced tunneling process. Our expressions for populations are in excellent agreement with the gross temporal profiles of exact numerical solutions. We compare the semi-classical and quantum dynamics in the triangle and establish the conditions for their equivalence.
Dimensions of monomial varieties
Creators: name: Nathanson, Melvyn B.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Algebraic Geometry (math.AG)
subject: FOS: Mathematics
subject: 13C15, 12D99, 12-01, 13-01

description: The dimensions of certain varieties defined by monomials are computed using only high school algebra.
description: 11 pages. Minor improvements and corrected typos
Effect of inquiry-based learning with GeoGebra for geometric thinking and mathematical achievement of Grade-8 students
Creators: name: Natthaphon Hongthong
Publisher: name: Faculty of Science, Ubon Ratchathani University
Year: 2023
Subjects: Geometric thinking
Inquiry-based learning
GeoGebra

description: Journal of Science and Science Education, 6, 2, 320-332
Interface magnetism and electronic structure: ZnO(0001)/Co3O4(111)
Creators: name: Kupchak, Igor
name: Serpak, Natalia
name: Shkrebtii, Anatoli
name: Hayn, Roland
Publisher: name: arXiv
Year: 2017
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: We have studied the structural, electronic and magnetic properties of spinel $\rm Co_3O_4$(111) surfaces and their interfaces with ZnO (0001) using density functional theory (DFT) within the Generalized Gradient Approximation with on-site Coulomb repulsion term (GGA+U). Two possible forms of spinel surface, containing $\rm Co^{2+} $ and $\rm Co^{3+} $ ions and terminated with either cobalt or oxygen ions were considered, as well as their interface with zinc oxide. Our calculations demonstrate that $\rm Co^{3+} $ ions attain non-zero magnetic moments at the surface and interface, in contrast to the bulk, where they are not magnetic, leading to the ferromagnetic ordering. Since heavily Co-doped ZnO samples can contain $\rm Co_3O_4 $ secondary phase, such a magnetic ordering at the interface might explain the origin of the magnetism in these diluted magnetic semiconductors (DMS).
description: 20 pages, 4 figures, 2 table
Il progetto Skills4EOSC: una rete europea di centri di competenza per gli Open Science Commons
Creators: name: Lazzeri, Emma
Publisher: name: Zenodo
Year: 2022
Subjects: Open Science
Skills
Comeptence
FAIR
EOSC

description: Il progetto Skills4EOSC: una rete europea di centri di competenza per gli Open Science Commons presentazione per la GenOA Week 2022
The Adiabatically Deformed Ensemble: Engineering Non-Thermal States of Matter
Creators: name: Kennes, D. M.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: We propose a route towards engineering non-thermal states of matter, which show largely unexplored physics. The main idea relies on the adiabatic passage of a thermal ensemble under slow variations of the system Hamiltonian. If the temperature of the initial thermal ensemble is either zero or infinite the ensemble after the passage is a simple thermal one with the same vanishing or infinite temperature. However, for any finite non-zero temperature intriguing non-thermal ensembles can be achieved. We exemplify this in: (a) a single oscillator (b) a dimerized interacting one dimensional chain of spinless fermions, (c) a BCS-type superconductor and (d) the topological Kitaev chain. We solve these models with a combination of methods; either exactly, numerically using the density matrix renormalization group (DMRG) or within an approximate functional renormalization group (FRG) scheme. The designed states show strongly non-thermal behavior in each of the considered models. For example, for the chain of spinless fermions we exemplify how long ranged non-thermal power-law correlations can be stabilized and for the Kitaev chain we elucidate how the non-thermal ensemble can largely alter the transition temperature separating topological and trivial phases.
description: 11 pages, 9 figures, version as published
Second Law based definition of passivity/activity of devices
Creators: name: Sundqvist, Kyle
name: Ferry, David K.
name: Kish, Laszlo B.
Publisher: name: arXiv
Year: 2017
Subjects: subject: General Physics (physics.gen-ph)
subject: FOS: Physical sciences

description: Recently, our efforts to clarify the old question, if a memristor is a passive or active device [1], triggered debates between engineers, who have had advanced definitions of passivity/activity of devices, and physicists with significantly different views about this seemingly simple question. This debate triggered our efforts to test the well-known engineering concepts about passivity/activity in a deeper way, challenging them by statistical physics. It is shown that the advanced engineering definition of passivity/activity of devices is self-contradictory when a thermodynamical system executing Johnson-Nyquist noise is present. A new, statistical physical, self-consistent definition based on the Second Law of Thermodynamics is introduced. It is also shown that, in a system with uniform temperature distribution, any rectifier circuitry that can rectify thermal noise must contain an active circuit element, according to both the engineering and statistical physical definitions.
description: Accepted for publication in Physics Letters A. (August 17, 2017)
An elementary proof for the Krull dimension of a polynomial ring
Creators: name: Nathanson, Melvyn B.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Commutative Algebra (math.AC)
subject: FOS: Mathematics
subject: 13C15, 12D99, 12-01, 13-01

description: This is an expository paper in which it is proved that, for every infinite field ${\mathbf{F}}$, the polynomial ring ${\mathbf{F}}[t_1,\ldots, t_n]$ has Krull dimension $n$. The proof uses only "high school algebra" and the rudiments of undergraduate "abstract algebra."
description: 14 pages. Improved exposition and corrected typos
Star Cluster Formation in a Turbulent Molecular Cloud Self-Regulated by Photo-Ionisation Feedback
Creators: name: Gavagnin, Elena
name: Bleuler, Andreas
name: Rosdahl, Joakim
name: Teyssier, Romain
Publisher: name: arXiv
Year: 2017
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: Most stars in the Galaxy are believed to be formed within star clusters from collapsing molecular clouds. However, the complete process of star formation, from the parent cloud to a gas-free star cluster, is still poorly understood. We perform radiation-hydrodynamical simulations of the collapse of a turbulent molecular cloud using the RAMSES-RT code. Stars are modelled using sink particles, from which we self-consistently follow the propagation of the ionising radiation. We study how different feedback models affect the gas expulsion from the cloud and how they shape the final properties of the emerging star cluster. We find that the star formation efficiency is lower for stronger feedback models. Feedback also changes the high mass end of the stellar mass function. Stronger feedback also allows the establishment of a lower density star cluster, which can maintain a virial or sub-virial state. In the absence of feedback, the star formation efficiency is very high, as well as the final stellar density. As a result, high energy close encounters make the cluster evaporate quickly. Other indicators, such as mass segregation, statistics of multiple systems and escaping stars confirm this picture. Observations of young star clusters are in best agreement with our strong feedback simulation.
description: 20 pages, 14 figures. Accepted by MNRAS
Approximate reversal of quantum Gaussian dynamics
Creators: name: Lami, Ludovico
name: Das, Siddhartha
name: Wilde, Mark M.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Quantum Physics (quant-ph)
subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: Recently, there has been focus on determining the conditions under which the data processing inequality for quantum relative entropy is satisfied with approximate equality. The solution of the exact equality case is due to Petz, who showed that the quantum relative entropy between two quantum states stays the same after the action of a quantum channel if and only if there is a \textit{reversal channel} that recovers the original states after the channel acts. Furthermore, this reversal channel can be constructed explicitly and is now called the \textit{Petz recovery map}. Recent developments have shown that a variation of the Petz recovery map works well for recovery in the case of approximate equality of the data processing inequality. Our main contribution here is a proof that bosonic Gaussian states and channels possess a particular closure property, namely, that the Petz recovery map associated to a bosonic Gaussian state $σ$ and a bosonic Gaussian channel $\mathcal{N}$ is itself a bosonic Gaussian channel. We furthermore give an explicit construction of the Petz recovery map in this case, in terms of the mean vector and covariance matrix of the state $σ$ and the Gaussian specification of the channel $\mathcal{N}$.
description: v2: 36 pages, minor changes
Light-by-light forward scattering sum rules for charmonium states
Creators: name: Danilkin, Igor
name: Vanderhaeghen, Marc
Publisher: name: arXiv
Year: 2017
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We apply three forward light-by-light scattering sum rules to charmonium states. We show that these sum rules imply a cancellation between charmonium bound state contributions, which are mostly known from the $γγ$ decay widths of these states, and continuum contributions above $D \bar D$ threshold, for which we provide a duality estimate. We also show that two of these sum rules allow to predict the yet unmeasured $γ^\ast γ$ coupling of the $χ_{c1}(1P)$ state, which can be tested at present high-luminosity $e^+ e^-$ colliders.
description: 9 pages, 2 figures
Arrested relaxation in an isolated molecular ultracold plasma
Creators: name: Haenel, R.
name: Schulz-Weiling, M.
name: Sous, J.
name: Sadeghi, H.
name: Aghigh, M.
name: Melo, L.
name: Keller, J. S.
name: Grant, E. R.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Plasma Physics (physics.plasm-ph)
subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Atomic Physics (physics.atom-ph)
subject: FOS: Physical sciences

description: Spontaneous avalanche to plasma splits the core of an ellipsoidal Rydberg gas of nitric oxide. Ambipolar expansion first quenches the electron temperature of this core plasma. Then, long-range, resonant charge transfer from ballistic ions to frozen Rydberg molecules in the wings of the ellipsoid quenches the centre-of-mass ion/Rydberg molecule velocity distribution. This sequence of steps gives rise to a remarkable mechanics of self-assembly, in which the kinetic energy of initially formed hot electrons and ions drives an observed separation of plasma volumes. These dynamics adiabatically sequester energy in a reservoir of mass transport, starting a process that anneals separating volumes to form an apparent glass of strongly coupled ions and electrons. Short-time electron spectroscopy provides experimental evidence for complete ionization. The long lifetime of this system, particularly its stability with respect to recombination and neutral dissociation, suggests that this transformation affords a robust state of arrested relaxation, far from thermal equilibrium.
On intersection forms of definite 4-manifolds bounded by a rational homology 3-sphere
Creators: name: Choe, Dong Heon
name: Park, Kyungbae
Publisher: name: arXiv
Year: 2017
Subjects: subject: Geometric Topology (math.GT)
subject: Number Theory (math.NT)
subject: FOS: Mathematics

description: We show that, if a rational homology 3-sphere $Y$ bounds a positive definite smooth 4-manifold, then there are finitely many negative definite lattices, up to the stable-equivalence, which can be realized as the intersection form of a smooth 4-manifold bounded by $Y$. To this end, we make use of constraints on definite forms bounded by $Y$ induced from Donaldson's diagonalization theorem, and correction term invariants due to Frøyshov, and Ozsváth and Szabó. In particular, we prove that all spherical 3-manifolds satisfy such finiteness property.
description: 17 pages, 5 figures; Typos fixed. We added more results including properties on spherical 3-manifolds. The version to appear in Topology and its Applications
Search for light bosons in decays of the 125 GeV Higgs boson in proton-proton collisions at sqrt(s) = 8 TeV
Creators: name: CMS Collaboration
Publisher: name: arXiv
Year: 2017
Subjects: subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: A search is presented for decays beyond the standard model of the 125 GeV Higgs bosons to a pair of light bosons, based on models with extended scalar sectors. Light boson masses between 5 and 62.5 GeV are probed in final states containing four tau leptons, two muons and two b quarks, or two muons and two tau leptons. The results are from data in proton-proton collisions corresponding to an integrated luminosity of 19.7 inverse femtobarns, accumulated by the CMS experiment at the LHC at a center-of-mass energy of 8 TeV. No evidence for such exotic decays is found in the data. Upper limits are set on the product of the cross section and branching fraction for several signal processes. The results are also compared to predictions of two-Higgs-doublet models, including those with an additional scalar singlet.
description: Replaced with the published version. Added the journal reference and DOI. All the figures and tables can be found at http://cms-results.web.cern.ch/cms-results/public-results/publications/HIG-16-015 (CMS Public Pages)
Dynamical depinning of chiral domain walls
Creators: name: Moretti, Simone
name: Voto, Michele
name: Martinez, Eduardo
Publisher: name: arXiv
Year: 2017
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: The domain wall depinning field represents the minimum magnetic field needed to move a domain wall, typically pinned by samples' disorder or patterned constrictions. Conventionally, such field is considered independent on the Gilbert damping since it is assumed to be the field at which the Zeeman energy equals the pinning energy barrier (both damping independent). Here, we analyse numerically the domain wall depinning field as function of the Gilbert damping in a system with perpendicular magnetic anisotropy and Dzyaloshinskii-Moriya interaction. Contrary to expectations, we find that the depinning field depends on the Gilbert damping and that it strongly decreases for small damping parameters. We explain this dependence with a simple one-dimensional model and we show that the reduction of the depinning field is related to the internal domain wall dynamics, proportional to the Dzyaloshinskii-Moriya interaction, and the finite size of the pinning barriers.