nils-herrmann/clean_scirepeval huggingface dataset:
Global computation in a poorly connected world: fast rumor spreading with no dependence on conductance

In this paper, we study the question of how efficiently a collection of interconnected nodes can perform a global computation in the GOSSIP model of communication. In this model, nodes do not know the global topology of the network, and they may only initiate contact with a single neighbor in each round. This model contrasts with the much less restrictive LOCAL model, where a node may simultaneously communicate with all of its neighbors in a single round. A basic question in this setting is how many rounds of communication are required for the information dissemination problem, in which each node has some piece of information and is required to collect all others. In the LOCAL model, this is quite simple: each node broadcasts all of its information in each round, and the number of rounds required will be equal to the diameter of the underlying communication graph. In the GOSSIP model, each node must independently choose a single neighbor to contact, and the lack of global information makes it difficult to make any sort of principled choice. As such, researchers have focused on the uniform gossip algorithm, in which each node independently selects a neighbor uniformly at random. When the graph is well-connected, this works quite well. In a string of beautiful papers, researchers proved a sequence of successively stronger bounds on the number of rounds required in terms of the conductance φ and graph size n, culminating in a bound of O(φ-1 log n).
 In this paper, we show that a fairly simple modification of the protocol gives an algorithm that solves the information dissemination problem in at most O(D + polylog (n)) rounds in a network of diameter D, with no dependence on the conductance. This is at most an additive polylogarithmic factor from the trivial lower bound of D, which applies even in the LOCAL model.
 In fact, we prove that something stronger is true: any algorithm that requires T rounds in the LOCAL model can be simulated in O(T + polylog(n)) rounds in the GOSSIP model. We thus prove that these two models of distributed computation are essentially equivalent.
Data Mining and Machine-Learning in Time-Domain Discovery & Classification

The changing heavens have played a central role in the scientific effort of astronomers for centuries. Galileo's synoptic observations of the moons of Jupiter and the phases of Venus starting in 1610, provided strong refutation of Ptolemaic cosmology. In more modern times, the discovery of a relationship between period and luminosity in some pulsational variable stars led to the inference of the size of the Milky Way, the distance scale to the nearest galaxies, and the expansion of the Universe. Distant explosions of supernovae were used to uncover the existence of dark energy and provide a precise numerical account of dark matter. Indeed, time-domain observations of transient events and variable stars, as a technique, influences a broad diversity of pursuits in the entire astronomy endeavor. While, at a fundamental level, the nature of the scientific pursuit remains unchanged, the advent of astronomy as a data-driven discipline presents fundamental challenges to the way in which the scientific process must now be conducted. Digital images (and data cubes) are not only getting larger, there are more of them. On logistical grounds, this taxes storage and transport systems. But it also implies that the intimate connection that astronomers have always enjoyed with their data---from collection to processing to analysis to inference---necessarily must evolve. The pathway to scientific inference is now influenced (if not driven by) modern automation processes, computing, data-mining and machine learning. The emerging reliance on computation and machine learning is a general one, but the time-domain aspect of the data and the objects of interest presents some unique challenges, which we describe and explore in this chapter.
Light Charged Higgs bosons at the LHC in 2HDMs

We present a discussion of light charged Higgs boson searches at the Large Hadron Collider (LHC) in CP-conserving 2-Higgs Doublet Models (2HDMs). Taking into account all available experimental and theoretical constraints we review all possible processes that would allow for a detection of such a particle with a mass below the top quark mass. Two different types of processes are analysed: one that depends only on tan beta and on the charged Higgs boson mass because it involves only the charged Higgs boson Yukawa couplings; the other that depends on almost all model parameters, mainly due to the presence of Higgs self-couplings. We discuss the regions of parameter space of 2HDMs that can be covered be each type of process and define some guidelines for experimental searches at the LHC.
Hidden Variables in Bipartite Networks

We introduce and study random bipartite networks with hidden variables. Nodes in these networks are characterized by hidden variables that control the appearance of links between node pairs. We derive analytic expressions for the degree distribution, degree correlations, the distribution of the number of common neighbors, and the bipartite clustering coefficient in these networks. We also establish the relationship between degrees of nodes in original bipartite networks and in their unipartite projections. We further demonstrate how hidden variable formalism can be applied to analyze topological properties of networks in certain bipartite network models, and verify our analytical results in numerical simulations.
Detection of trend changes in time series using bayesian inference.

Change points in time series are perceived as isolated singularities where two regular trends of a given signal do not match. The detection of such transitions is of fundamental interest for the understanding of the system's internal dynamics or external forcings. In practice observational noise makes it difficult to detect such change points in time series. In this work we elaborate on a bayesian algorithm to estimate the location of the singularities and to quantify their credibility. We validate the performance and sensitivity of our inference method by estimating change points of synthetic data sets. As an application we use our algorithm to analyze the annual flow volume of the Nile River at Aswan from 1871 to 1970, where we confirm a well-established significant transition point within the time series.
A Gauge-Invariant Reorganization of Thermal Gauge Theory

This dissertation is devoted to the study of thermodynamics for quantum gaugetheories. The poor convergence of quantum field theory at finite temperaturehas been the main obstacle in the practical applications of thermal QCD fordecades. In this dissertation I apply hard-thermal-loop perturbation theory,which is a gauge-invariant reorganization of the conventional perturbativeexpansion for quantum gauge theories to the thermodynamics of QED andYang-Mills theory to three-loop order. For the Abelian case, I present acalculation of the free energy of a hot gas of electrons and photons byexpanding in a power series in $m_D/T$, $m_f/T$ and $e^2$, where $m_D$ and$m_f$ are the photon and electron thermal masses, respectively, and $e$ is thecoupling constant. I demonstrate that the hard-thermal-loop perturbationreorganization improves the convergence of the successive approximations to theQED free energy at large coupling, $e \sim 2$. For the non-Abelian case, Ipresent a calculation of the free energy of a hot gas of gluons by expanding ina power series in $m_D/T$ and $g^2$, where $m_D$ is the gluon thermal mass and$g$ is the coupling constant. I show that at three-loop order hard-thermal-loopperturbation theory is compatible with lattice results for the pressure, energydensity, and entropy down to temperatures $T \sim 2-3\;T_c$. The resultssuggest that HTLpt provides a systematic framework that can be used tocalculate static and dynamic quantities for temperatures relevant at LHC.
An efficient and principled method for detecting communities in networks

A fundamental problem in the analysis of network data is the detection of network communities, groups of densely interconnected nodes, which may be overlapping or disjoint. Here we describe a method for finding overlapping communities based on a principled statistical approach using generative network models. We show how the method can be implemented using a fast, closed-form expectation-maximization algorithm that allows us to analyze networks of millions of nodes in reasonable running times. We test the method both on real-world networks and on synthetic benchmarks and find that it gives results competitive with previous methods. We also show that the same approach can be used to extract nonoverlapping community divisions via a relaxation method, and demonstrate that the algorithm is competitively fast and accurate for the nonoverlapping problem.
Electromagnetic moments of quasi‐stable baryons

We address electromagnetic properties of quasi‐stable baryons in the context of chiral extrapolations of lattice QCD results. For particles near their decay threshold we show that an application of a small external magnetic field changes the particle’s energy in a non‐analytic way. The conventional electromagnetic moments are only well‐defined when the background field B satisfies |eB|/2M*≪|M*−M−m| where M* is the mass of the resonance and M, m the masses of the decay products. A direct application of this situation is the chiral extrapolation of the Δ(1232)‐isobar electromagnetic properties. We discuss such an extrapolation of the Δ(1232)‐isobar magnetic dipole, electric quadrupole and magnetic octupole moments by a covariant chiral effective field theory.
A cold and slow molecular beam.

Employing a two-stage cryogenic buffer gas cell, we produce a cold, hydrodynamically extracted beam of calcium monohydride molecules with a near effusive velocity distribution. Beam dynamics, thermalization and slowing are studied using laser spectroscopy. The key to this hybrid, effusive-like beam source is a "slowing cell" placed immediately after a hydrodynamic, cryogenic source [Patterson et al.,  2007, 126, 154307]. The resulting CaH beams are created in two regimes. In one regime, a modestly boosted beam has a forward velocity of v(f) = 65 m s(-1), a narrow velocity spread, and a flux of 10(9) molecules per pulse. In the other regime, our slowest beam has a forward velocity of v(f) = 40 m s(-1), a longitudinal temperature of 3.6 K, and a flux of 5 × 10(8) molecules per pulse.
SIR epidemics in monogamous populations with recombination

We study the propagation of an SIR (susceptible-infectious-recovered) disease over an agent population which, at any instant, is fully divided into couples of agents. Couples are occasionally allowed to exchange their members. This process of couple recombination can compensate the instantaneous disconnection of the interaction pattern and thus allow for the propagation of the infection. We study the incidence of the disease as a function of its infectivity and of the recombination rate of couples, thus characterizing the interplay between the epidemic dynamics and the evolution of the population's interaction pattern.
Habitable Planet Detection and Characterization with Far Infrared Coherent Interferometry

The characterization of extrasolar earth-like atmospheres for biosignatures remains one of the most compelling and elusive challenges in astronomy. Coronagraphy, nulling interferometry and free-ying occulters have been advanced as potential techniques to accomplish this gaol. In this paper, a complementary approach, coherent interferometry in the far infrared is considered. For an interferometer operating close to the quantum noise limit, a collecting area of 1000 m 2 and baselines of 200 m are sucient to detect an earth-like planet. The high spectral resolution achievable with coherent detection further enables unambiguous molecular inventory of an atmosphere and retrieval of atmospheric temperature-pressure-composition proles. The far-infrared is rich in molecular features, particularly transitions of the key biosignature molecules H2O and O3. The level of detail that can be obtained on atmospheres is such that the goals of detection and detailed characterization of biosignatures can be accomplished by the same mission. Hitherto, however, the majority of modeling eorts concerning the extrasolar planet atmospheres has been limited to the visible and thermal infrared regimes considered for coronagraphs and nulling interferometry. It is therefore worth seriously investigating the feasibility of such an architecture for a possible mission, and considering biosignatures that might be available in the far-infrared.
Aspects of noncommutative (1+1)-dimensional black holes

We present a comprehensive analysis of the spacetime structure and thermodynamics of (1 + 1)−dimensional black holes in a noncommutative framework. It is shown that a wider variety of solutions are possible than the commutative case considered previously in the literature. As expected, the introduction of a minimal length √ � cures singularity pathologies that plague the standard two-dimensional general relativistic case, where the latter solution is recovered at large length scales. Depending on the choice of input parameters (black hole mass M, cosmological constant �, etc...), black hole solutions with zero, up to six, horizons are possible. The associated thermodynamics allows for the either complete evaporation, or the production of black hole remnants.
An effective Z

We describe a method to couple Z' gauge bosons to the standard model (SM), without charging the SM fields under the U(1)', but instead through effective higher-dimension operators. This method allows complete control over the tree-level couplings of the Z' and does not require altering the structure of any of the SM couplings, nor does it contain anomalies or require introduction of fields in nonstandard SM representations. Moreover, such interactions arise from simple renormalizable extensions of the SM—the addition of vectorlike matter that mixes with SM fermions when the U(1)' is broken. We apply effective Z' models as explanations of various recent anomalies: the D0 same-sign dimuon asymmetry, the CDF W+di-jet excess and the CDF top forward-backward asymmetry. In the case of the W+di-jet excess we also discuss several complementary analyses that may shed light on the nature of the discrepancy. We consider the possibility of non-Abelian groups, and discuss implications for the phenomenology of dark matter as well.
On Order and Randomness: A View from the Edge of Chaos

The recognition of the agency of the knower has enormously enriched our understanding of knowledge production. There is a growing realization that what we know about how we know affects our interpretation of reality. This realization informs the perspective of this paper. As a case study, the paper looks at the problem of randomness vs. determinism. It argues that this problem is not intrinsic to nature but is rather a product of the epistemological approach that does not pay attention to the process of the construction of knowledge. In contrast to the current one-sided solutions of the problem that represent reality as either random or deterministic, this paper argues that reality is neither random nor deterministic. Neither randomness nor determinism exists on its own. Rather, randomness and determinism are ways in which reality appears to us as a result of a one-sided view of the relationship between systems and subsystems in the process of construction.
Ultra stable and very low noise signal source using a cryocooled sapphire oscillator for VLBI

Here we present the design and implementation of a novel frequency synthesizer based on low phase noise digital dividers and a direct digital synthesizer. The synthesis produces two low noise accurate and tunable signals at 10 MHz and 100 MHz. We report on the measured residual phase noise and frequency stability of the synthesizer, and estimate the total frequency stability, which can be expected from the synthesizer seeded with a signal near 11.2 GHz from an ultra-stable cryocooled sapphire oscillator. 
The synthesizer residual single sideband phase noise, at 1 Hz offset, on 10 MHz and 100 MHz signals, respectively, were measured to be -135 dBc/Hz and -130 dBc/Hz. Their intrinsic frequency stability contributions, on the 10 MHz and 100 MHz signals, respectively, were measured as sigma_y = 9 x 10^-15 and sigma_y = 2.2 x 10^-15, at 1 s integration time. 
The Allan Deviation of the total fractional frequency noise on the 10 MHz and 100 MHz signals derived from the synthesizer with the cryocooled sapphire oscillator, may be estimated as sigma_y = 5.2 x 10^-15 \tau ^-1 + 3.6 x 10^-15 \tau ^-1/2 + 4 x 10^-16 and sigma_y = 2 x 10^-15 \tau ^-1/2 + 3 x 10^-16, respectively, for 1 s < \tau < 10^4 s. 
We also calculate the coherence function, (a figure of merit in VLBI) for observation frequencies of 100 GHz, 230 GHz and 345 GHz, when using the cryocooled sapphire oscillator and an hydrogen maser. The results show that the cryocooled sapphire oscillator offers a significant advantage at frequencies above 100 GHz.
THE FIRST YEAR OF THE LARGE HADRON COLLIDER: A BRIEF REVIEW

The first year of LHC data taking provided an integrated luminosity of about 35 pb-1 in proton–proton collisions at . The accelerator and the experiments have demonstrated an excellent performance. The experiments have obtained important physics results in many areas, ranging from tests of the Standard Model to searches for new particles. Among other results, the physics highlights have been the measurements of the W-, Z-boson and production cross-sections, improved limits on supersymmetric and other hypothetical particles and the observation of jet-quenching, elliptical flow and J/ψ suppression in lead–lead collisions at .
Robustness and Contagion in the International Financial Network

The recent financial crisis of 2008 and the 2011 indebtedness of Greece highlight the importance of understanding the structure of the global financial network. In this paper we set out to analyze and characterize this network, as captured by the IMF Coordinated Portfolio Investment Survey (CPIS), in two ways. First, through an adaptation of the "error and attack" methodology , we show that the network is of the "robust-yet-fragile" type, a topology found in a wide variety of evolved networks. We compare these results against four common null-models, generated only from first-order statistics of the empirical data. In addition, we suggest a fifth, log-normal model, which generates networks that seem to match the empirical one more closely. Still, this model does not account for several higher order network statistics, which reenforces the added value of the higher-order analysis. Second, using loss-given-default dynamics , we model financial interdependence and potential cascading of financial distress through the network. Preliminary simulations indicate that default by a single relatively small country like Greece can be absorbed by the network, but that default in combination with defaults of other PIGS countries (Portugal, Ireland, and Spain) could lead to a massive extinction cascade in the global economy.
AN ARECIBO SEARCH FOR PULSARS AND TRANSIENT SOURCES IN M33

We report on a systematic and sensitive search for pulsars and transient sources in the nearby spiral galaxy M33, conducted at 1.4 GHz with the Arecibo telescope's seven-beam receiver system, ALFA. Data were searched for both periodic and aperiodic sources, up to 1000 pc cm−3 in dispersion measure and on timescales from ∼50 μs to several seconds. The galaxy was sampled with 12 ALFA pointings, or 84 pixels in total, each of which was searched for 2–3 hr. We describe the observations, search methodologies, and analysis strategies applicable to multibeam systems, and comment on the data quality and statistics of spurious events that arise due to radio frequency interference. While these searches have not led to any conclusive signals of periodic or transient nature that originate in the galaxy, they illustrate some of the underlying challenges and difficulties in such searches and the efficacy of simultaneous multiple beams in the analysis of search output. The implied limits are ≲5 μJy Mpc2 in luminosity (at 1400 MHz) for periodic sources in M33 with duty cycles ≲5%. For short-duration transient signals (with pulse widths ≲100 μs ), the limiting peak flux density is 100 mJy, which would correspond to a 5σ detection of bright giant pulses (∼20 kJy) from Crab-like pulsars if located at the distance of M33. We discuss the implications of our null results for various source populations within the galaxy and comment on the future prospects to conduct even more sensitive searches with the upcoming next-generation instruments including the Square Kilometer Array and its pathfinders.
Scale invariance via a phase of slow expansion

We consider a cosmological scenario in which a scale-invariant spectrum of curvature perturbations is generated by a rapidly-evolving equation of state on a slowly expanding background. This scenario generalizes the "adiabatic ekpyrotic" mechanism proposed recently in . Whereas the original proposal assumed a slowly contracting background, the present work shows that the mechanism works equally well on an expanding background. This greatly expands the realm of broader cosmological scenarios in which this mechanism can be embedded. We present a phase space analysis and show that both the expanding and contracting versions of the scenario are dynamical attractors, with the expanding branch having a broader basin of attraction. In both cases, a finite range of scale invariant modes can be generated within the regime of validity of perturbation theory.
Finite-momentum Bose-Einstein condensates in shaken two-dimensional square optical lattices

We consider ultracold bosons in a two-dimensional square optical lattice described by the Bose-Hubbard model. In addition, an external time-dependent sinusoidal force is applied to the system, which shakes the lattice along one of the diagonals. The effect of the shaking is to renormalize the nearest-neighbor-hopping coefficients, which can be arbitrarily reduced, can vanish, or can even change sign, depending on the shaking parameter. Therefore, it is necessary to account for higher-order-hopping terms, which are renormalized differently by the shaking, and to introduce anisotropy into the problem. We show that the competition between these different hopping terms leads to finite-momentum condensates with a momentum that may be tuned via the strength of the shaking. We calculate the boundaries between the Mott insulator and the different superfluid phases and present the time-of-flight images expected to be observed experimentally. Our results open up possibilities for the realization of bosonic analogs of the Fulde, Ferrel, Larkin, and Ovchinnikov phase describing inhomogeneous superconductivity
Exact-exchange density functional theory for neutron drops

We compute the ground-state properties of finite systems of neutrons in an external harmonic trap, interacting via the Minnesota potential, using the "exact-exchange" form of orbital-dependent density functional theory. We compare our results with Hartree-Fock calculations and find very close agreement. Within the context of the interaction studied, we conclude that this simple orbital-dependent functional brings conventional nuclear density functional theory to the level of Hartree-Fock in an ab initio fashion. Our work is a first step toward higher order ab initio nuclear functionals based on realistic nucleon-nucleon interactions.