Results for "Daniel Huber"

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Precision Stellar Astrophysics in the Kepler EraApr 25 2016The study of fundamental properties (such as temperatures, radii, masses, and ages) and interior processes (such as convection and angular momentum transport) of stars has implications on various topics in astrophysics, ranging from the evolution of galaxies ... More
N-Body Simulations of Open, Self-Gravitating SystemsJan 16 2001Astrophysical systems differ often in two points from classical thermodynamical systems: 1.) They are open and 2.) gravity is a dominant factor. Both modifies the homogeneous equilibrium structure, known from classical thermodynamics. In order to study ... More
Dynamics in a Bistable-Element-Network with Delayed Coupling and Local NoiseOct 14 2003The dynamics of an ensemble of bistable elements under the influence of noise and with global time-delayed coupling is studied numerically by using a Langevin description and analytically by using 1) a Gaussian approximation and 2) a dichotomous model. ... More
Complexity of Discrete Energy Minimization ProblemsJul 29 2016Discrete energy minimization is widely-used in computer vision and machine learning for problems such as MAP inference in graphical models. The problem, in general, is notoriously intractable, and finding the global optimal solution is known to be NP-hard. ... More
Asteroseismology of Eclipsing Binary Stars in the Kepler EraApr 29 2014Eclipsing binary stars have long served as benchmark systems to measure fundamental stellar properties. In the past few decades, asteroseismology - the study of stellar pulsations - has emerged as a new powerful tool to study the structure and evolution ... More
Asteroseismology of Exoplanet Host StarsNov 23 2015Nov 29 2015Asteroseismology is among the most powerful observational tools to determine fundamental properties of stars. Space-based photometry has recently enabled the systematic detection of oscillations in exoplanet host stars, allowing a combination of asteroseismology ... More
Asteroseismology of Cool StarsNov 04 2014The measurement of oscillations excited by surface convection is a powerful method to study the structure and evolution of cool stars. CoRoT and Kepler have initiated a revolution in asteroseismology by detecting oscillations in thousands of stars from ... More
Proving the Generation of Genuine Multipartite Entanglement in a Single-Neutron Interferometer ExperimentDec 05 2012Feb 24 2013We present experimental evidence of the generation of distinct types of genuine multipartite entanglement between three degrees of freedom, two internal and one external degree of freedom, within single-neutron quantum systems. This is achieved via the ... More
Self-Gravitating N-Body Systems out of EquilibriumOct 19 2000Real physical systems are often maintained off equilibrium by energy or matter flows. If these systems are far from equilibrium then the thermodynamical branch become unstable and fluctuations can lead them to other more stable states. These new states ... More
Scaling Laws in Self-Gravitating DisksApr 16 1999The interstellar medium (ISM) reveals strongly inhomogeneous structures at every scale. These structures do not seem completely random since they obey certain power laws. Larson's law (\citeyear{Larson81}) $\sigma \propto R^{\delta}$ and the plausible ... More
Long-Range Correlations in Self-Gravitating N-Body SystemsJan 29 2002Observed self-gravitating systems reveal often fragmented non-equilibrium structures that feature characteristic long-range correlations. However, models accounting for non-linear structure growth are not always consistent with observations and a better ... More
Lumpy Structures in Self-Gravitating DisksMay 29 2001Following Toomre & Kalnajs (1991), local models of slightly dissipative self-gravitating disks show how inhomogeneous structures can be maintained over several galaxy rotations. Their basic physical ingredients are self-gravity, dissipation and differential ... More
Fragmentation in Kinematically Cold DisksJan 16 2001Gravity is scale free. Thus gravity may form similar structures in self-gravitating systems on different scales. Indeed, observations of the interstellar medium, spiral disks and cosmic structures, reveal similar characteristics. The structures in these ... More
Calculating asteroseismic diagrams for solar-like oscillationsSep 15 2011With the success of the Kepler and CoRoT missions, the number of stars with detected solar-like oscillations has increased by several orders of magnitude, for the first time we are able to perform large-scale ensemble asteroseismology of these stars. ... More
Asteroseismology of 16000 Kepler red giants: Global oscillation parameters, Masses, and radiiFeb 13 2018The Kepler mission has provided exquisite data to perform an ensemble asteroseismic analysis on evolved stars. In this work we systematically characterize solar-like oscillations and granulation for 16,094 oscillating red giants, using end-of-mission ... More
A Mean-Field Model for Extended Stochastic Systems with Distributed Time DelaysJan 26 2005A network of noisy bistable elements with global time-delayed couplings is considered. A dichotomous mean field model has recently been developed describing the collective dynamics in such systems with uniform time delays near the bifurcation points. ... More
Design and Implementation of a Semantic Dialogue System for RadiologistsJan 25 2017This chapter describes a semantic dialogue system for radiologists in a comprehensive case study within the large-scale MEDICO project. MEDICO addresses the need for advanced semantic technologies in the search for medical image and patient data. The ... More
The Impact of Stellar Multiplicity on Planetary Systems, I.: The Ruinous Influence of Close Binary CompanionsApr 19 2016The dynamical influence of binary companions is expected to profoundly influence planetary systems. However, the difficulty of identifying planets in binary systems has left the magnitude of this effect uncertain; despite numerous theoretical hurdles ... More
Tidally Induced Oscillations and Orbital Decay in Compact Triple-Star SystemsNov 29 2012Jan 28 2013We investigate the nature of tidal effects in compact triple-star systems. The hierarchical structure of a triple system produces tidal forcing at high frequencies unobtainable in binary systems, allowing for the tidal excitation of high frequency p-modes ... More
Cooperative Dynamics in a Network of Stochastic Elements with Delayed FeedbackMar 11 2005Networks of globally coupled, noise activated, bistable elements with connection time delays are considered. The dynamics of these systems is studied numerically using a Langevin description and analytically using (1) a Gaussian approximation as well ... More
Exploring competing density order in the ionic Hubbard model with ultracold fermionsMar 18 2015Sep 25 2015We realize and study the ionic Hubbard model using an interacting two-component gas of fermionic atoms loaded into an optical lattice. The bipartite lattice has honeycomb geometry with a staggered energy-offset that explicitly breaks the inversion symmetry. ... More
Asteroseismology of 1523 misclassified red giants using $\textit{Kepler}$ dataAug 20 2016We analysed solar-like oscillations in 1523 $\textit{Kepler}$ red giants which have previously been misclassified as subgiants, with predicted $\nu_{\rm max}$ values (based on the Kepler Input Catalogue) between 280$\mu$Hz to 700$\mu$Hz. We report the ... More
Automated extraction of oscillation parameters for Kepler observations of solar-type starsOct 15 2009The recent launch of the Kepler space telescope brings the opportunity to study oscillations systematically in large numbers of solar-like stars. In the framework of the asteroFLAG project, we have developed an automated pipeline to estimate global oscillation ... More
Highly indistinguishable and strongly entangled photons from symmetric GaAs quantum dotsOct 21 2016The development of scalable sources of non-classical light is fundamental to unlock the technological potential of quantum photonics\cite{Kimble:Nat2008}. Among the systems under investigation, semiconductor quantum dots are currently emerging as near-optimal ... More
Modelling Kepler Red Giants in Eclipsing Binaries:Calibrating the Mixing Length Parameter with AsteroseismologyDec 05 2017Stellar models rely on a number of free parameters. High-quality observations of eclipsing binary stars observed by Kepler offer a great opportunity to calibrate model parameters for evolved stars. Our study focuses on six Kepler red giants with the goal ... More
Photometry of Very Bright Stars with Kepler and K2 Smear DataSep 30 2015High-precision time series photometry with the Kepler satellite has been crucial to our understanding both of exoplanets, and via asteroseismology, of stellar physics. After the failure of two reaction wheels, the Kepler satellite has been repurposed ... More
Probing the Deep End of the Milky Way with New Oscillating Kepler GiantsNov 14 2016The Kepler mission has been a success in both exoplanet search and stellar physics studies. Red giants have actually been quite a highlight in the Kepler scene. The Kepler long and almost continuous four-year observations allowed us to detect oscillations ... More
Flicker as a tool for characterizing planets through Asterodensity ProfilingMar 20 2014Variability in the time series brightness of a star on a timescale of 8 hours, known as 'flicker', has been previously demonstrated to serve as a proxy for the surface gravity of a star by Bastien et al. (2013). Although surface gravity is crucial for ... More
Site-resolved imaging of a fermionic Mott insulatorNov 19 2015Mar 21 2016The complexity of quantum many-body systems originates from the interplay of strong interactions, quantum statistics, and the large number of quantum-mechanical degrees of freedom. Probing these systems on a microscopic level with single-site resolution ... More
A theory of theta functions to the quintic baseApr 02 2013Properties of four quintic theta functions are developed in parallel with those of the classical Jacobi null theta functions. The quintic theta functions are shown to satisfy analogues of Jacobi's quartic theta function identity and counterparts of Jacobi's ... More
Time-periodic Néel wall motionsJun 24 2010In thin ferromagnetic films, the predominance of the magnetic shape anisotropy leads to in-plane magnetizations. The simplest domain wall in this geometry is the one-dimensional Neel wall that connects two magnetizations of opposite sign by a planar 180 ... More
Perfect Sampling Using Bounding ChainsMay 14 2004Bounding chains are a technique that offers three benefits to Markov chain practitioners: a theoretical bound on the mixing time of the chain under restricted conditions, experimental bounds on the mixing time of the chain that are provably accurate and ... More
Large eccentricity, low mutual inclination: the three-dimensional architecture of a hierarchical system of giant planetsMay 20 2014Jul 12 2014We establish the three-dimensional architecture of the Kepler-419 (previously KOI-1474) system to be eccentric yet with a low mutual inclination. Kepler-419b is a warm Jupiter at semi-major axis a = 0.370 +0.007/-0.006 AU with a large eccentricity e=0.85 ... More
Orbital Architectures of Planet-Hosting Binaries: I. Forming Five Small Planets in the Truncated Disk of Kepler-444ADec 10 2015We present the first results from our Keck program investigating the orbital architectures of planet-hosting multiple star systems. Kepler-444 is a metal-poor triple star system that hosts five sub-Earth-sized planets orbiting the primary star (Kepler-444A), ... More
Testing stellar evolution models with the retired A star HD 185351Oct 19 2016The physical parameters of the retired A star HD 185351 were analysed in great detail by Johnson et al. (2014) using interferometry, spectroscopy and asteroseismology. Results from all independent methods are consistent with HD 185351 having a mass in ... More
A simple model to describe intrinsic stellar noise for exoplanet detection around red giantsOct 27 2016In spite of the huge advances in exoplanet research provided by the NASA Kepler Mission, there remain only a small number of transit detections around evolved stars. Here we present a reformulation of the noise properties of red-giant stars, where the ... More
Kepler's Unparalleled Exploration of the Time DimensionSep 04 2013We show that the Kepler spacecraft in two-reaction wheel mode of operation is very well suited for the study of eclipsing binary star systems. Continued observations of the Kepler field will provide the most enduring and long-term valuable science. It ... More
An exploratory study of Yang-Mills three-point functions at non-zero temperatureNov 18 2016Results for three-point functions of Landau gauge Yang-Mills theory at non-vanishing temperature are presented and compared to lattice results. It is found that the three-gluon vertex is enhanced for temperatures below the phase transition. At very low ... More
Shrinkage estimators for prediction out-of-sample: Conditional performanceSep 05 2012Nov 29 2013We find that, in a linear model, the James-Stein estimator, which dominates the maximum-likelihood estimator in terms of its in-sample prediction error, can perform poorly compared to the maximum-likelihood estimator in out-of-sample prediction. We give ... More
On cubic multisections of Eisenstein seriesApr 02 2013A systematic procedure for generating cubic multisections of Eisenstein series is given. The relevant series are determined from Fourier expansions for Eisenstein series by restricting the congruence class of the summation index modulo three. We prove ... More
Weak randomness in device independent quantum key distribution and the advantage of using high dimensional entanglementJan 11 2013Sep 11 2013We show that in device independent quantum key distribution protocols the privacy of randomness is of crucial importance. For sublinear test sample sizes even the slightest guessing probability by an eavesdropper will completely compromise security. We ... More
Critical geometry of two-dimensional passive scalar turbulenceNov 10 2000Passive scalars advected by a magnetically driven two-dimensional turbulent flow are analyzed using methods of statistical topography. The passive tracer concentration is interpreted as the height of a random surface and the scaling properties of its ... More
Equivariant Bloch-Kato conjecture and non-abelian Iwasawa Main ConjectureJul 30 2002This is a contribution to the ICM 2002. We explain the relation between the (equivariant) Bloch-Kato conjecture for special values of L-functions and the Main Conjecture of (non-abelian) Iwasawa theory. On the way we will discuss briefly the case of Dirichlet ... More
Differential equations for septic theta functionsApr 02 2013We demonstrate that quotients of septic theta functions appearing in S. Ramanujan's Notebooks and in F. Klein's work satisfy a new coupled system of nonlinear differential equations with interesting symmetric form. This differential system bears a close ... More
Sparse Bayesian vector autoregressions in huge dimensionsApr 11 2017We develop a Bayesian vector autoregressive (VAR) model that is capable of handling vast dimensional information sets. Three features are introduced to permit reliable estimation of the model. First, we assume that the reduced-form errors in the VAR feature ... More
Linear temperature dependence of electron spin resonance linewidths in La0.7Ca0.3MnO3 and YBaMn2O6Sep 24 2013We analyze recent electron spin resonance (ESR) experiments in La0.7Ca0.3MnO3 and YBaMn2O6 focusing on the behavior of the linewidth at high temperatures where it is a linear function of the temperature. Noting that the g-factors of the resonances are ... More
Towards Minimizing k-Submodular FunctionsSep 21 2013In this paper we investigate k-submodular functions. This natural family of discrete functions includes submodular and bisubmodular functions as the special cases k = 1 and k = 2 respectively. In particular we generalize the known Min-Max-Theorem for ... More
Bloch-Kato conjecture and main conjecture of Iwasawa theory for Dirichlet charactersJan 09 2001Feb 25 2002This is the completely revised version of math.AG/0101071.
Random construction of interpolating sets for high dimensional integrationDec 16 2011Many high dimensional integrals can be reduced to the problem of finding the relative measures of two sets. Often one set will be exponentially larger than the other, making it difficult to compare the sizes. A standard method of dealing with this problem ... More
Solving the mode identification problem in asteroseismology of F stars observed with KeplerMay 02 2012Asteroseismology of F-type stars has been hindered by an ambiguity in identification of their oscillation modes. The regular mode pattern that makes this task trivial in cooler stars is masked by increased linewidths. The absolute mode frequencies, encapsulated ... More
K2-97b: A (Re-?)Inflated Planet Orbiting a Red Giant StarJun 19 2016Nov 29 2016Strongly irradiated giant planets are observed to have radii larger than thermal evolution models predict. Although these inflated planets have been known for over fifteen years, it is unclear whether their inflation is caused by deposition of energy ... More
MOST detects variability on tau Bootis possibly induced by its planetary companionFeb 20 2008(abridged) There is considerable interest in the possible interaction between parent stars and giant planetary companions in 51 Peg-type systems. We demonstrate from MOST satellite photometry and Ca II K line emission that there has been a persistent, ... More
Bounds on the artificial phase transition for perfect simulation of repulsive point processesOct 15 2010Repulsive point processes arise in models where competition forces entities to be more spread apart than if placed independently. Simulation of these types of processes can be accomplished using dominated coupling from the past with a running time that ... More
Modeling Kepler Observations of Solar-like Oscillations in the Red-giant Star HD 186355Sep 05 2011Nov 28 2011We have analysed oscillations of the red giant star HD 186355 observed by the NASA Kepler satellite. The data consist of the first five quarters of science operations of Kepler, which cover about 13 months. The high-precision time-series data allow us ... More
Influence of nano confinement on nematic liquid crystalsAug 14 2012We explore the nematic ordering of the rod-like liquid crystals 5CB and 6CB, embedded into parallel-aligned nanochannels in mesoporous silicon and silica membranes as a function of mean channel radius (4.7<=R <=8.3 nm), and thus geometrical confinement ... More
Optimal excitation conditions for indistinguishable photons from quantum dotsJul 27 2015Nov 26 2015In this letter, we present a detailed, all optical study of the influence of different excitation schemes on the indistinguishability of single photons from a single InAs quantum dot. For this study, we measure the Hong-Ou-Mandel interference of consecutive ... More
Asteroseismology of Solar-type stars with Kepler III. Ground-based DataMay 06 2010We report on the ground-based follow-up program of spectroscopic and photometric observations of solar-like asteroseismic targets for the Kepler space mission. These stars constitute a large group of more than thousand objects which are the subject of ... More
MOST photometry of the RRd Lyrae variable AQ Leo: Two radial modes, 32 combination frequencies, and beyondMay 31 2007Jul 09 2007Highly precise and nearly uninterrupted optical photometry of the RR Lyrae star AQ Leo was obtained with the MOST (Microvariability & Oscillations of STars) satellite over 34.4 days in February-March 2005. AQ Leo was the first known double-mode RR Lyrae ... More
Differential expression analysis for multiple conditionsOct 13 2014As high-throughput sequencing has become common practice, the cost of sequencing large amounts of genetic data has been drastically reduced, leading to much larger data sets for analysis. One important task is to identify biological conditions that lead ... More
The quark propagator in QCD and $G_2$ QCDDec 02 2016QCD-like theories provide testing grounds for truncations of functional equations at non-zero density, since comparisons with lattice results are possible due to the absence of the sign problem. As a first step towards such a comparison, we determine ... More
Coherent pumping of a Mott insulator: Fermi golden rule versus Rabi oscillationsDec 02 2008Feb 26 2009Cold atoms provide a unique arena to study many-body systems far from equilibrium. Furthermore, novel phases in cold atom systems are conveniently investigated by dynamical probes pushing the system out of equilibrium. Here, we discuss the pumping of ... More
Scanning SQUID susceptometers with sub-micron spatial resolutionMay 31 2016Jul 25 2016Superconducting QUantum Interference Device (SQUID) microscopy has excellent magnetic field sensitivity, but suffers from modest spatial resolution when compared with other scanning probes. This spatial resolution is determined by both the size of the ... More
The TESS-HERMES survey Data Release 1: high-resolution spectroscopy of the TESS southern continuous viewing zoneJul 18 2017Sep 30 2017The Transiting Exoplanet Survey Satellite (TESS) will provide high precision time-series photometry for millions of stars with at least a half-hour cadence. Of particular interest are the circular regions of 12-degree radius centered around the ecliptic ... More
Standing on the shoulders of Dwarfs: the Kepler asteroseismic LEGACY sample II - radii, masses, and agesNov 27 2016Nov 29 2016We use asteroseismic data from the Kepler satellite to determine fundamental stellar properties of the 66 main-sequence targets observed for at least one full year by the mission. We distributed tens of individual oscillation frequencies extracted from ... More
Standing on the shoulders of Dwarfs: the Kepler asteroseismic LEGACY sample II - radii, masses, and agesNov 27 2016Dec 02 2016We use asteroseismic data from the Kepler satellite to determine fundamental stellar properties of the 66 main-sequence targets observed for at least one full year by the mission. We distributed tens of individual oscillation frequencies extracted from ... More
Absolutely maximally entangled states of seven qubits do not existAug 22 2016Pure multiparticle quantum states are called absolutely maximally entangled if all reduced states obtained by tracing out at least half of the particles are maximally mixed. We prove that a seven-qubit state whose three-body marginals are all maximally ... More
Structural transformations of even-numbered n-alkanes confined in mesoporesOct 02 2006The n-alkanes C12H26, C14H30, and C16H34 have been imbibed and solidified in mesoporous Vycor glass with a mean pore diameter of 10nm. The samples have been investigated by x-ray diffractometry and calorimetric measurements. The structures and phase sequences ... More
Transforming phylogenetic networks: Moving beyond tree spaceJan 08 2016Phylogenetic networks are a generalization of phylogenetic trees that are used to represent reticulate evolution. Unrooted phylogenetic networks form a special class of such networks, which naturally generalize unrooted phylogenetic trees. In this paper ... More
Lattice calculation of low energy constants with Ginsparg-Wilson type fermionsSep 01 2005Nov 08 2005We present a quenched lattice calculation of low energy constants using the chirally improved Dirac operator. Several lattice sizes at different lattice spacings are studied. We systematically compare various methods for computing these quantities, using ... More
Electric dipole moment constraints on minimal electroweak baryogenesisSep 29 2006Mar 17 2007We study the simplest generic extension of the Standard Model which allows for conventional electroweak baryogenesis, through the addition of dimension six operators in the Higgs sector. At least one such operator is required to be CP-odd, and we study ... More
Passivity and practical work extraction using Gaussian operationsAug 17 2016Nov 16 2016Quantum states that can yield work in a cyclical Hamiltonian process form one of the primary resources in the context of quantum thermodynamics. Conversely, states whose average energy cannot be lowered by unitary transformations are called passive. However, ... More
On the Analytic Structure of Scalar Glueball OperatorsJan 15 2013The correlator of the square of the Yang-Mills field-strength tensor corresponds to a scalar glueball, i.e., to a bound-state formed by gluonic ingredients only. It has quantum numbers 0++ and its mass, as predicted by different theoretical approaches, ... More
On the infrared scaling solution of SU(N) Yang-Mills theories in the maximally Abelian gaugeApr 12 2009Jul 06 2010An improved method for extracting infrared exponents from functional equations is presented. The generalizations introduced allow for an analysis of quite complicated systems such as Yang-Mills theory in the maximally Abelian gauge. Assuming the absence ... More
Infrared Behavior of 3-Point Functions in Landau Gauge Yang-Mills TheoryDec 23 2008The three-gluon and ghost-gluon vertices of Landau gauge Yang-Mills theory are investigated in the low momentum regime. Due to ghost dominance in the infrared we can use the known power law behavior for the propagators to determine analytically the complete ... More
Compatibility of neutron star masses and hyperon coupling constantsNov 30 1998It is shown that the modern equations of state for neutron star matter based on microscopic calculations of symmetric and asymmetric nuclear matter are compatible with the lower bound on the maximum neutron-star mass for a certain range of hyperon coupling ... More
Sophisticated and small versus simple and sizeable: When does it pay off to introduce drifting coefficients in Bayesian VARs?Nov 01 2017Nov 29 2017We assess the relationship between model size and complexity in the time-varying parameter VAR framework via thorough predictive exercises for the Euro Area, the United Kingdom and the United States. It turns out that sophisticated dynamics through drifting ... More
Antineutrino reactor safeguards - a case studyDec 06 2013Feb 13 2014Antineutrinos have been proposed as a means of reactor safeguards for more than 30 years and there has been impressive experimental progress in neutrino detection. In this paper we conduct, for the first time, a case study of the application of antineutrino ... More
Combining dark matter detectors and electron-capture sources to hunt for new physics in the neutrino sectorJun 18 2014Oct 14 2014In this letter we point out the possibility to study new physics in the neutrino sector using dark matter detectors based on liquid xenon. These are characterized by very good spatial resolution and extremely low thresholds for electron recoil energies. ... More
Super-Activation of Quantum SteeringOct 04 2016We consider Einstein-Podolsky-Rosen steering in the regime where the parties can perform collective measurements on many copies of a given shared entangled state. We derive a simple and efficient condition for guaranteeing that an entangled state is $k$-copy ... More
Absolutely maximally entangled states of seven qubits do not existAug 22 2016Nov 07 2016Pure multiparticle quantum states are called absolutely maximally entangled if all reduced states obtained by tracing out at least half of the particles are maximally mixed. We provide a method to characterize these states for a general multiparticle ... More
On the Lifetime of Quasi-Stationary States in Non-Relativistic QEDSep 24 2007We consider resonances in the Pauli-Fierz model of non-relativistic QED. We use and slightly modify the analysis developed by Bach, Froehlich, and Sigal to obtain an upper and lower bound on the lifetime of quasi-stationary states.
Balanced modular parameterizationsMay 27 2014For prime levels $5 \le p \le 19$, sets of $\Gamma_{0}(p)$-permuted theta quotients are constructed that generate the graded rings of modular forms of positive integer weight for $\Gamma_{1}(p)$. An explicit formulation of the permutation representation ... More
The Summed Start-up Costs in a Unit Commitment ProblemMar 04 2015We consider the sum of the incurred start-up costs of a single unit in a Unit Commitment problem. Our major result is a correspondence between the facets of its epigraph and some binary trees for concave start-up cost functions CU, which is bijective ... More
Coupled regularization with multiple data discrepanciesNov 30 2017We consider a class of regularization methods for inverse problems where a coupled regularization is employed for the simultaneous reconstruction of data from multiple sources. Applications for such a setting can be found in multi-spectral or multi-modality ... More
The univalence axiom in cubical setsOct 30 2017In this note we show that Voevodsky's univalence axiom holds in the model of type theory based on symmetric cubical sets. We will also discuss Swan's construction of the identity type in this variation of cubical sets. This proves that we have a model ... More
A supercharacter approach to Heilbronn sumsDec 04 2013Jul 07 2015Various algebraic properties of Heilbronn's exponential sum can be deduced through the use of supercharacter theory, a novel extension of classical character theory due to Diaconis-Isaacs and Andr\'e. This perspective yields a variety of formulas and ... More
How to determine the branch points of correlation functions in Euclidean spaceApr 12 2013Two-point correlators represented by either perturbative or non-perturbative integral equations in Euclidean space are considered. In general, it is difficult to determine the analytic structure of arbitrary correlators analytically. When relying on numerical ... More
On the analytic structure of scalar glueball operators at Born levelDec 10 2012Mar 13 2013We study the analytic structure of the two-point function of the operator F2 which is expected to describe a scalar glueball. The calculation of the involved integrals is complicated by nonanalytic structures in the integrands, which we take into account ... More
Infrared singularities in Landau gauge Yang-Mills theoryJan 17 2008May 11 2010We present a more detailed picture of the infrared regime of Landau gauge Yang-Mills theory. This is done within a novel framework that allows one to take into account the influence of finite scales within an infrared power counting analysis. We find ... More
Infrared Behavior of Three-Point Functions in Landau Gauge Yang-Mills TheoryDec 22 2008Jun 16 2009Analytic solutions for the three-gluon and ghost-gluon vertices in Landau gauge Yang-Mills theory at low momenta are presented in terms of hypergeometric series. They do not only show the expected scaling behavior but also additional kinematic divergences ... More
A New Approach To Time Varying Parameters in Vector Autoregressive ModelsJul 15 2016Jan 12 2018We propose a flexible means of estimating vector autoregressions with time-varying parameters (TVP-VARs) by introducing a latent threshold process that is driven by the absolute size of parameter changes. This enables us to dynamically detect whether ... More
On Higher Inductive Types in Cubical Type TheoryFeb 04 2018Cubical type theory provides a constructive justification to certain aspects of homotopy type theory such as Voevodsky's univalence axiom. This makes many extensionality principles, like function and propositional extensionality, directly provable in ... More
Sounding open clusters: asteroseismic constraints from Kepler on the properties of NGC 6791 and NGC 6819Feb 10 2011We present initial results on some of the properties of open clusters NGC 6791 and NGC 6819 derived from asteroseismic data obtained by NASA's Kepler mission. In addition to estimating the mass, radius and log g of stars on the red-giant branch of these ... More
Asteroseismology of the open clusters NGC 6791, NGC 6811, and NGC 6819 from nineteen months of Kepler photometryMay 17 2012Aug 07 2012We studied solar-like oscillations in 115 red giants in the three open clusters NGC 6791, NGC 6811, and NGC 6819, based on photometric data covering more than 19 months with NASA's Kepler space telescope. We present the asteroseismic diagrams of the asymptotic ... More
Three Temperate Neptunes Orbiting Nearby StarsJun 30 2016We present the discovery of three modestly-irradiated, roughly Neptune-mass planets orbiting three nearby Solar-type stars. HD 42618 b has a minimum mass of $15.4 \pm 2.4$ M$_{\oplus}$, a semi-major axis of 0.55 AU, an equilibrium temperature of 337 K, ... More
Precision Orbit of $δ$ Delphini and Prospects for Astrometric Detection of ExoplanetsFeb 01 2018Combining visual and spectroscopic orbits of binary stars leads to a determination of the full 3D orbit, individual masses, and distance to the system. We present a full analysis of the evolved binary system $\delta$ Delphini using astrometric data from ... More
Paranematic-to-nematic ordering of a binary mixture of rod-like liquid crystals confined in cylindrical nanochannelsJun 19 2014We explore the optical birefringence of the nematic binary mixtures 6CB$_{1-x}$7CB$_x$ ($0~\le~x~\le~1$) imbibed into parallel-aligned nanochannels of mesoporous alumina and silica membranes for channel radii of $3.4~\le~R~\le 21.0$ nm. The results are ... More
A Staged Muon Accelerator Facility For Neutrino and Collider PhysicsFeb 05 2015Muon-based facilities offer unique potential to provide capabilities at both the Intensity Frontier with Neutrino Factories and the Energy Frontier with Muon Colliders. They rely on a novel technology with challenging parameters, for which the feasibility ... More
Capillary Condensation, Freezing, and Melting in Silica Nanopores: A Sorption Isotherm and Scanning Calorimetry Study on Nitrogen in Mesoporous SBA-15Feb 08 2012Condensation, melting and freezing of nitrogen in a powder of mesoporous silica grains (SBA-15) has been studied by combined volumetric sorption isotherm and scanning calorimetry measurements. Within the mean field model of Saam and Cole for vapor condensation ... More
Polymorphism of the glass former ethanol confined in mesoporous siliconMay 12 2010X-ray diffraction patterns of ethanol confined in parallel-aligned channels of approx. 10 nm diameter and 50 micrometer length in mesoporous silicon have been recorded as a function of filling fraction, temperature and for varying cooling and heating ... More