nils-herrmann/clean_scirepeval huggingface dataset:
Amplitudes for space-like separations and causality

This paper explores whether quantum eld theory allows the events of emission and absorption of a single particle to be separated by a space-like interval without violating Lorentz symmetries and causality. Although the answer is indeed armative, tradition- ally such eects have been considered negligible. We show that for suciently light mass eigenstates such processes can become signicant over macroscopic length scales. A critical review of the historical literature reveals various shortcomings of the standard methods; specically, one nds that they are restricted to states for which the expectation value of momentum vanishes. Furthermore, the results obtained here correct Feynman's analysis of this subject. A formalism is thus developed that allows the description of states with non-zero momentum, which is then applied to the OPERA and ICARUS neutrino-speed experiments. For OPERA we choose a mass in the nano electron-volt range and nd that although our formalism predicts a non-zero detection probability for an early arrival time of 60 ns, the predicted event distribution is maximal on the light-cone. Consequently, our prediction does not reproduce the peak at 60 ns reported by the OPERA collabora- tion. Turning to the ICARUS experiment, we note that while the collaboration reported an average time of ight that is consistent with the speed of light, the event data with its associated uncertainties nevertheless indicates that some of the detection events are separated from their corresponding emission events by a space-like interval. For a micro electron-volt mass range, this is in agreement with the here reported formalism. We thus raise the possibility of employing high-precision neutrino-speed experiments to determine the absolute masses of neutrino mass eigenstates. Finally, it is argued that the predicted space-like amplitudes are consistent with the emperical data on SN1987a.
Bogoliubov's Vision: Quasiaverages and Broken Symmetry to Quantum Protectorate and Emergence

In the present interdisciplinary review we focus on the applications of the symmetry principles to quantum and statistical physics in connection with some other branches of science. The profound and innovative idea of quasiaverages formulated by N.N. Bogoliubov, gives the so-called macro-objectivation of the degeneracy in domain of quantum statistical mechanics, quantum field theory and in the quantum physics in general. We discuss the complementary unifying ideas of modern physics, namely: spontaneous symmetry breaking, quantum protectorate and emergence. The interrelation of the concepts of symmetry breaking, quasiaverages and quantum protectorate was analyzed in the context of quantum theory and statistical physics. The chief purposes of this paper were to demonstrate the connection and interrelation of these conceptual advances of the many-body physics and to try to show explicitly that those concepts, though different in details, have a certain common features. Several problems in the field of statistical physics of complex materials and systems (e.g. the chirality of molecules) and the foundations of the microscopic theory of magnetism and superconductivity were discussed in relation to these ideas.
Quis Pendit Ipsa Pretia: Facebook Valuation and Diagnostic of a Bubble Based on Nonlinear Demographic Dynamics

Cauwels and Sornette present a novel methodology to determine the fundamental value of firms in the social networking sector, motivated by recent realized IPOs and by reports that suggest sky-high valuations of firms such as Facebook, Groupon, LinkedIn Corp., Pandora Media, Inc., Twitter, and Zynga. The authors’ valuation of these firms is based on two assumptions:1) revenues and profits of a social networking firm are inherently linked to its user base through a direct channel that has no equivalent in other sectors, and 2) the growth in the number of users can be calibrated with standard logistic growth models, which allows for reliable extrapolations of the size of the business at long time horizons. Cauwels and Sornette illustrate the methodology with a detailed analysis of Facebook, one of the biggest of the social media giants. A clear signature of a change of regime, occurring in 2010 in the growth of the number of users, is observed. The change of regime is a move from a pure exponential behavior (a paradigm for unlimited growth) to a logistic function with asymptotic plateau (a paradigm for growth in competition). The authors consider three different scenarios: a base case, high-growth, and extreme-growth scenario. Using a discount factor of 5%, a profit margin of 29% and $3.50 of revenues per user per year yields a value of Facebook of $15.3 billion in the base case scenario, $20.2 billion in the high-growth scenario, and $32.9 billion in the extreme-growth scenario. According to the authors’ methodology, this implies that Facebook needs to increase its profit per user before the IPO by a factor of 3 to 6 in the base case scenario, 2.5 to 5 in the high-growth scenario, and 1.5 to 3 in the extreme-growth scenario in order to meet the current, widespread high expectations. To prove the wider applicability of their methodology, the analysis is repeated for Groupon, the well-known deal-of-the-day website, that went public in November 2011.The results are in line with the Facebook analysis. Customer growth will plateau. By not taking this fundamental property of the growth process into consideration, estimates of the Facebook IPO are wildly overpriced.
ASTEROSEISMIC DIAGRAMS FROM A SURVEY OF SOLAR-LIKE OSCILLATIONS WITH KEPLER

Photometric observations made by the NASA Kepler Mission have led to a dramatic increase in the number of main-sequence and subgiant stars with detected solar-like oscillations. We present an ensemble asteroseismic analysis of 76 solar-type stars. Using frequencies determined from the Kepler time-series photometry, we have measured three asteroseismic parameters that characterize the oscillations: the large frequency separation (Δν), the small frequency separation between modes of l = 0 and l = 2 (δν02), and the dimensionless offset (ϵ). These measurements allow us to construct asteroseismic diagrams, namely the so-called Christensen–Dalsgaard diagram of δν02 versus Δν, and the recently re-introduced ϵ diagram. We compare the Kepler results with previously observed solar-type stars and with theoretical models. The positions of stars in these diagrams places constraints on their masses and ages. Additionally, we confirm the observational relationship between ϵ and Teff that allows for the unambiguous determination of radial order and should help resolve the problem of mode identification in F stars.
ECOSMOG: An Efficient Code for Simulating Modified Gravity

We introduce a new code, ECOSMOG, to run N-body simulations for a wide class of modified gravity and dynamical dark energy theories. These theories generally have one or more new dynamical degrees of freedom, the dynamics of which are governed by their (usually rather nonlinear) equations of motion. Solving these non-linear equations has been a great challenge in cosmology. Our code is based on the RAMSES code, which solves the Poisson equation on adaptively refined meshes to gain high resolutions in the high-density regions. We have added a solver for the extra degree(s) of freedom and performed numerous tests for the f(R) gravity model as an example to show its reliability. We find that much higher efficiency could be achieved compared with other existing mesh/grid-based codes thanks to two new features of the present code: (1) the efficient parallelisation and (2) the usage of the multigrid relaxation to solve the extra equation(s) on both the regular domain grid and refinements, giving much faster convergence even under much more stringent convergence criteria. This code is designed for performing high-accuracy, high-resolution and large-volume cosmological simulations for modified gravity and general dark energy theories, which can be utilised to test gravity and the dark energy hypothesis using the upcoming and future deep and high-resolution galaxy surveys.
Lattice diffeomorphism invariance

We propose a lattice counterpart of diffeomorphism symmetry in the continuum. A functional integral for quantum gravity is regularized on a discrete set of space-time points, with fermionic or bosonic lattice fields. When the space-time points are positioned as discrete points of a continuous manifold, the lattice action can be reformulated in terms of average fields within local cells and lattice derivatives. Lattice diffeomorphism invariance is realized if the action is independent of the positioning of the space-time points. Regular as well as rather irregular lattices are then described by the same action. Lattice diffeomorphism invariance implies that the continuum limit and the quantum effective action are invariant under general coordinate transformations - the basic ingredient for general relativity. In our approach the lattice diffeomorphism invariant actions are formulated without introducing a metric or other geometrical objects as fundamental degrees of freedom. The metric rather arises as the expectation value of a suitable collective field. As examples, we present lattice diffeomorphism invariant actions for a bosonic non-linear sigma-model and lattice spinor gravity.
SOME CONSIDERATIONS ON DISCRETE QUANTUM GRAVITY

Recent results in Local Regge Calculus are confronted with Spin-Foam Formalism. Introducing Barrett–Crane Quantization in Local Regge Calculus makes it possible to associate a unique Spin jh with an hinge h, fulfilling one of the requirements of Spin-Foam definition. It is shown that inter-twiner terms of Spin-Foam can follow from the closure constraint in Local Regge Calculus.
Radio bursts from superconducting strings

We show that radio bursts from cusps on superconducting strings are linearly polarized, thus providing a signature that can be used to distinguish them from astrophysical sources. We write the event rate of string-generated radio transients in terms of observational variables, namely, the event duration and flux. Assuming a canonical set of observational parameters, we find that the burst event rate can be quite reasonable, e.g., order ten a year for grand unified strings with 100 TeV currents, and a lack of observed radio bursts can potentially place strong constraints on particle physics models.
Static electromagnetic fields and charged black holes in general covariant theory of Hořava-Lifshitz gravity

In this paper, we study electromeganetic static spacetimes in the nonrelativisitc general covariant theory of the Hořava-Lifshitz (HL) gravity, proposed recently by Hořava and Melby-Thompson, and present all the electric static solutions, which represent the generalization of the Reissner-Nordstrom solution found in Einstein's general relativity (GR). The global/local structures of spacetimes in the HL theory in general are different from those given in GR, because the dispersion relations of test particles now contain high-order momentum terms, so the speeds of these particles are unbounded in the ultraviolet (UV). As a result, the conception of light-cones defined in GR becomes invalid and test particles do not follow geodesics. To study black holes in the HL theory, we adopt the geometrical optical approximations, and define a horizon as a (two-closed) surface that is free of spacetime singularities and on which massless test particles are infinitely redshifted. With such a definition, we show that some of our solutions give rise to (charged) black holes, although the radii of their horizons in general depend on the energies of the test particles.
Branching Dynamics of Viral Information Spreading

Despite its importance for rumors or innovations propagation, peer-to-peer collaboration, social networking, or marketing, the dynamics of information spreading is not well understood. Since the diffusion depends on the heterogeneous patterns of human behavior and is driven by the participants' decisions, its propagation dynamics shows surprising properties not explained by traditional epidemic or contagion models. Here we present a detailed analysis of our study of real viral marketing campaigns where tracking the propagation of a controlled message allowed us to analyze the structure and dynamics of a diffusion graph involving over 31,000 individuals. We found that information spreading displays a non-Markovian branching dynamics that can be modeled by a two-step Bellman-Harris branching process that generalizes the static models known in the literature and incorporates the high variability of human behavior. It explains accurately all the features of information propagation under the "tipping point" and can be used for prediction and management of viral information spreading processes.
The microwave sky after one year of Planck operations

The ESA Planck satellite, launched on May 14th, 2009, is the third generation space mission dedicated to the measurement of the Cosmic Microwave Background (CMB), the first light in the Universe. Planck observes the full sky in nine frequency bands from 30 to 857 GHz and is designed to measure the CMB anisotropies with an unprecedented combination of sensitivity, angular resolution and control of systematic effects. In this presentation we summarise the Planck instruments performance and discuss the main scientific results obtained after one year of operations in the fields of galactic and extragalactic astrophysics.
Characterizing and Modeling Citation Dynamics

Citation distributions are crucial for the analysis and modeling of the activity of scientists. We investigated bibliometric data of papers published in journals of the American Physical Society, searching for the type of function which best describes the observed citation distributions. We used the goodness of fit with Kolmogorov-Smirnov statistics for three classes of functions: log-normal, simple power law and shifted power law. The shifted power law turns out to be the most reliable hypothesis for all citation networks we derived, which correspond to different time spans. We find that citation dynamics is characterized by bursts, usually occurring within a few years since publication of a paper, and the burst size spans several orders of magnitude. We also investigated the microscopic mechanisms for the evolution of citation networks, by proposing a linear preferential attachment with time dependent initial attractiveness. The model successfully reproduces the empirical citation distributions and accounts for the presence of citation bursts as well.
Halo scale predictions of symmetron modified gravity

We offer predictions of symmetron modified gravity in the neighborhood of realistic dark matter halos. The predictions for the fifth force are obtained by solving the nonlinear symmetron equation of motion in the spherical NFW approximation. In addition, we compare the three major known screening mechanisms: Vainshtein, Chameleon, and Symmetron around such dark matter halos, emphasizing the significant differences between them and highlighting observational tests which exploit these differences. Finally, we demonstrate the host halo environmental screening effect (``blanket screening'') on smaller satellite halos by solving for the modified forces around a density profile which is the sum of satellite and approximate host components.
Nature of 3D Bose Gases near Resonance

Dmitry Borzov, Mohammad S. Mashayekhi, Shizhong Zhang, Jun-Liang Song and Fei Zhou Department of Physics and Astronomy, The University of British Columbia, Vancouver, B. C., Canada V6T1Z1 Department of Physics, The Ohio-State University, Columbus,Ohio 43210, USA Institute for Quantum Optics and Quantum Information of the Austrian Academy of Sciences, 6020 Innsbruck, Austria Institute for Advanced Studies,Tsinghua University, Beijing 100084, China (Dated: June 20, 2018)
Consensus in networks of mobile communicating agents.

Populations of mobile and communicating agents describe a vast array of technological and natural systems, ranging from sensor networks to animal groups. Here, we investigate how a group-level agreement may emerge in the continuously evolving network defined by the local interactions of the moving individuals. We adopt a general scheme of motion in two dimensions and we let the individuals interact through the minimal naming game, a prototypical scheme to investigate social consensus. We distinguish different regimes of convergence determined by the emission range of the agents and by their mobility, and we identify the corresponding scaling behaviors of the consensus time. In the same way, we rationalize also the behavior of the maximum memory used during the convergence process, which determines the minimum cognitive/storage capacity needed by the individuals. Overall, we believe that the simple and general model presented in this paper can represent a helpful reference for a better understanding of the behavior of populations of mobile agents.
Project 8: Using Radio Frequencies to Measure the Neutrino Mass

It is well known that the neutrino masses affect the shape of the energy spectrum of tritium beta-decay electrons. However, experiments have yet to measure that distortion. The Project 8 experiment proposes to measure the spectral distortion in a novel way: using radio-frequency techniques to detect and measure the energies of the beta-decay electrons. We plan on measuring the radiation created from the cyclotron motion of the electrons in a strong magnetic field. I will report on the status of a prototype that is designed to demonstrate single-electron detection at energies near the tritium endpoint, 18.6 keV. I will also discuss the possibilities for scaling up to a neutrino-mass experiment.
Black holes and boson stars with one Killing field in arbitrary odd dimensions

We extend the recent $D=5$ results of Dias, Horowitz, and Santos by finding asymptotically anti\char21{}de Sitter rotating black hole and boson star solutions with scalar hair in arbitrary odd spacetime dimension. Both the black holes and the boson stars are invariant under a single Killing vector field which corotates with the scalar field and, in the black hole case, is tangent to the generator of the horizon. Furthermore, we explicitly construct boson star and small black hole (${r}_{+}\ensuremath{\ll}\ensuremath{\ell}$) solutions perturbatively assuming a small amplitude for the scalar field, resulting in solutions valid for low energies and angular momenta. We find that just as in $D=5$, the angular momentum is primarily carried by the scalar field in $Dg5$, whereas unlike $D=5$ the energy is also primarily carried by the scalar field in $Dg5$; the thermodynamics in $D=5$ are governed by both the black hole and scalar field whereas in $Dg5$ they are governed primarily by the scalar field alone. We focus on cataloging these solutions for the spacetime dimensions of interest in string theory, namely $D=5,7,9,11$.
Hawking radiation for a Proca field in D-dimensions

We study the wave equation of a massive vector boson in the background of a $D$-dimensional Schwarzschild black hole. The mass term introduces a coupling between two physical degrees of freedom of the field, and we solve the resulting system of ordinary differential equations numerically, without decoupling. We show how to define decoupled transmission factors from an $\mathbf{S}$ matrix and compute them for various modes, masses, and space-time dimensions. The mass term lifts the degeneracy between transverse modes, in $D=4$, and excites the longitudinal modes, in particular, the $s$ wave. Moreover, it increases the contribution of waves with larger $\ensuremath{\ell}$, which can be dominant at intermediate energies. The transmission factors are then used to obtain the Hawking fluxes in this channel. Our results alert for the importance of modeling the longitudinal modes correctly, instead of treating them as decoupled scalars as they are in current black hole event generators; thus, they can be used to improve such generators for phenomenological studies of TeV gravity scenarios.
Using frequency maps to explore the distribution function of the Milky Way stellar halo

Resolved surveys of the Milky Way's stellar halo can obtain all 6 phase space coordinates of tens of thousands of individual stars, making it possible to compute their 3-dimensional orbits. When frequency mapping is applied to such orbits they also represent the underlying phase space distribution function since the orbits that the are drawn from 3. A frequency maps clearly separates out the major types of orbits that constitute the DF and their relative abundances. The structure of the frequency maps, especially the locations of resonant orbits, reflects the formation history and shape of the dark matter potential and its orientation relative to the disk. The application of frequency analysis to cosmological hydrodynamic simulations of disk galaxies shows that the orbital families occupied by halo stars and dark matter particles are very similar, implying that stellar halo orbits can be used to constrain the DF of the dark matter halo, possibly impacting the interpretation of results from direct dark matter detection experiments. An application of these methods to a sample of ~ 16,000 Milky Way halo and thick disk stars from the SDSS-SEGUE survey yields a frequency map with strong evidence for resonant trapping of halo stars by the Milky Way disk, in a manner predicted by controlled simulations in which the disk grows adiabatically. The application of frequency analysis methods to current and future phase space data for Milky Way halo stars will provide new insights into the formation history of the different components of the Galaxy and the DF of the halo.
From large scale gas compression to cluster formation in the Antennae overlap region

We present a detailed observational analysis of how merger-driven turbulence may regulate the star-formation efficiency during galaxy interactions and set the initial conditions for the formation of super star clusters. Using VLT/SINFONI, we obtained near-infrared imaging spectroscopy of a small region in the Antennae overlap region, coincident with the supergiant molecular cloud 2 (SGMC 2). We find extended H2 line emission across much of the 600 pc field-of-view, traced at sub-arcsecond spatial resolution. The data also reveal a compact H2 source with broad lines and a dynamical mass Mdyn ∼ 10 7 M� , which has no observable Brγ or K-band continuum emission, and no obvious counterpart in the 6 cm radio continuum. Line ratios indicate that the H2 emission of both sources is powered by shocks, making these lines a quantitative tracer of the dissipation of turbulent kinetic energy. The turbulence appears to be driven by the large-scale gas dynamics, and not by feedback from star formation. We propose a scenario where the H2 emission is related to the formation of bound clouds through accretion. The kinetic energy of the accreted gas drives the turbulence and powers the H2 emission. Broad H2 line widths of-order 150 km s −1 , similar to the velocity gradient of the gas across the field of view, support this idea. Within this interpretation, the compact H2 source could be a massive cloud on its way to form a super star cluster within the next few Myr. This scenario can be further tested with ALMA observations.