Results for "Maximilian N. Günther"

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Isometry groups of Lorentzian manifolds of finite volume and The local geometry of compact homogeneous Lorentz spacesJun 27 2011Oct 06 2011Based on the work of Adams and Stuck as well as on the work of Zeghib, we classify the Lie groups which can act isometrically and locally effectively on Lorentzian manifolds of finite volume. In the case that the corresponding Lie algebra contains a direct ... More
A New Yield Simulator for Transiting Planets and False Positives: Application to the Next Generation Transit SurveyNov 08 2016We present a yield simulator to predict the number and characteristics of planets, false positives and false alarms in transit surveys. The simulator is based on a galactic model and the planet occurrence rates measured by the Kepler mission. It takes ... More
NGTS-5b: a highly inflated planet offering insights into the sub-Jovian desertMay 07 2019Context: Planetary population analysis gives us insight into formation and evolution processes. For short-period planets, the subJovian desert has been discussed in recent years with regard to the planet population in the mass/period and radius/period ... More
The Critical Numbers of Rankin-Selberg Convolutions of Cohomological RepresentationsApr 14 2016May 30 2016We study the critical numbers of the Rankin-Selberg convolution of arbitrary pairs of cohomological cuspidal automorphic representations and we parametrize these critical numbers by certain 1-dimensional subrepresentations attached to the corresponding ... More
Robust Reference Frame Extraction from Unsteady 2D Vector Fields with Convolutional Neural NetworksMar 25 2019Robust feature extraction is an integral part of scientific visualization. In unsteady vector field analysis, researchers recently directed their attention towards the computation of near-steady reference frames for vortex extraction, which is a numerically ... More
TESS Discovery of a Transiting Super-Earth in the $π$ Mensae SystemSep 16 2018Nov 08 2018We report the detection of a transiting planet around $\pi$ Mensae (HD 39091), using data from the Transiting Exoplanet Survey Satellite (TESS). The solar-type host star is unusually bright (V=5.7) and was already known to host a Jovian planet on a highly ... More
A Super-Earth and two sub-Neptunes transiting the bright, nearby, and quiet M-dwarf TOI-270Mar 14 2019We report the Transiting Exoplanet Survey Satellite (TESS) discovery of three small planets transiting one of the brightest (K-mag 8.3) and nearest (22.5 parsec) M-dwarf hosts to date, TOI-270 (TIC 259377017). The system is observationally favourable, ... More
Superposition in Modulation Spaces with Ultradifferentiable WeightsMar 29 2016In the theory of nonlinear partial differential equations we need to explain superposition operators. For modulation spaces equipped with particular ultradifferentiable weights this was done in \cite{rrs}. In this paper we introduce a class of general ... More
Differentiability of the Evolution Map and Mackey ContinuityDec 20 2018Jan 18 2019We solve the differentiability problem for the evolution map in Milnor's infinite dimensional setting. We first show that the evolution map of each $C^k$-semiregular Lie group $G$ (for $k\in \mathbb{N}\sqcup\{\mathrm{lip},\infty\}$) admits a particular ... More
Regularity of Lie GroupsNov 09 2017Jul 03 2018We solve the regularity problem for Milnor's infinite dimensional Lie groups in the $C^0$-topological context, and provide necessary and sufficient regularity conditions for the standard setting ($C^k$-topology). We prove that the evolution map is $C^0$-continuous ... More
On the hardness of deciding the equality of the induced and the uniquely restricted matching numberDec 21 2018If $G(M)$ denotes the subgraph of a graph $G$ induced by the set of vertices that are covered by some matching $M$ in $G$, then $M$ is an induced or a uniquely restricted matching if $G(M)$ is $1$-regular or if $M$ is the unique perfect matching of $G(M)$, ... More
Invariant Connections in Loop Quantum GravityJul 19 2013Mar 22 2016Given a group $G$ and an abelian $C^*$-algebra $\mathfrak{A}$, the antihomomorphisms $\Theta\colon G\rightarrow \mathrm{Aut}(\mathfrak{A})$ are in one-to-one with those left actions $\Phi\colon G\times \mathrm{Spec}(\mathfrak{A})\rightarrow \mathrm{Spec}(\mathfrak{A})$ ... More
Analysis of quantum-state disturbance in a protective measurement of a spin-1/2 particleDec 09 2015A distinguishing feature of protective measurement is the possibility of obtaining information about expectation values while making the disturbance of the initial state arbitrarily small. Quantifying this state disturbance is of paramount importance. ... More
Uniqueness of Measures in Loop Quantum CosmologyFeb 26 2015Sep 30 2015In a paper of Ashtekar and Campiglia, residual diffeomorphisms have been used to single out the standard representation of the reduced holonomy-flux algebra in homogeneous loop quantum cosmology (LQC). We show that, in the homogeneous isotropic case, ... More
The Strong Trotter Property for Locally $μ$-convex Lie GroupsFeb 24 2018We show that an infinite dimensional Lie group in Milnor's sense has the strong Trotter property if it is locally $\mu$-convex. This is a continuity condition imposed on the Lie group multiplication that generalizes the triangle inequality for locally ... More
Dynamical self-averaging for a lattice Schrödinger equation with weak random potentialDec 25 2013Jun 20 2015We study the kinetic, weak coupling limit of the dynamics governed by a discrete random Schr\"odinger operator on $\mathbb{Z}^3$. For sequences of $\ell^2\left(\mathbb{Z}^3\right)$-bounded initial states and convergent initial Wigner transform, we prove ... More
Existence of a unique strong solution to the DMPK equationMay 15 2012Jan 08 2013For the transmission of electrons in a weakly disordered strip of material Dorokhov, Mello, Pereyra and Kumar (DMPK) proposed a diffusion process for the transfer matrices. The correspoding transmission eigenvalues satisfy the DMPK stochastic differential ... More
NGTS-4b: A sub-Neptune Transiting in the DesertSep 03 2018We report the discovery of NGTS-4b, a sub-Neptune-sized planet transiting a 13th magnitude K-dwarf in a 1.34d orbit. NGTS-4b has a mass M=$20.6\pm3.0$M_E and radius R=$3.18\pm0.26$R_E, which places it well within the so-called "Neptunian Desert". The ... More
Discrete Riemann surfaces based on quadrilateral cellular decompositionsNov 02 2015Mar 13 2017Our aim in this paper is to provide a theory of discrete Riemann surfaces based on quadrilateral cellular decompositions of Riemann surfaces together with their complex structure encoded by complex weights. Previous work, in particular of Mercat, mainly ... More
Computational Performance Evaluation of Two Integer Linear Programming Models for the Minimum Common String Partition ProblemJan 10 2015Mar 26 2015In the minimum common string partition (MCSP) problem two related input strings are given. "Related" refers to the property that both strings consist of the same set of letters appearing the same number of times in each of the two strings. The MCSP seeks ... More
Discrete complex analysis on planar quad-graphsMay 21 2015We develop a linear theory of discrete complex analysis on general quad-graphs, continuing and extending previous work of Duffin, Mercat, Kenyon, Chelkak and Smirnov on discrete complex analysis on rhombic quad-graphs. Our approach based on the medial ... More
On discrete integrable equations with convex variational principlesNov 27 2011May 20 2015We investigate the variational structure of discrete Laplace-type equations that are motivated by discrete integrable quad-equations. In particular, we explain why the reality conditions we consider should be all that are reasonable, and we derive sufficient ... More
Magic points in finance: Empirical integration for parametric option pricingNov 03 2015Nov 04 2016We propose an offline-online procedure for Fourier transform based option pricing. The method supports the acceleration of such essential tasks of mathematical finance as model calibration, real-time pricing, and, more generally, risk assessment and parameter ... More
Magic points in finance: Empirical integration for parametric option pricingNov 03 2015Nov 04 2015We propose an interpolation method for parametric option pricing tailored to the persistently recurring task of pricing liquid financial instruments. The method supports the acceleration of such essential tasks of mathematical finance as model calibration, ... More
An Eccentric Massive Jupiter Orbiting a Sub-Giant on a 9.5 Day Period Discovered in the Transiting Exoplanet Survey Satellite Full Frame ImagesJan 28 2019Apr 16 2019We report the discovery of TOI-172 b from the Transiting Exoplanet Survey Satellite (TESS) mission, a massive hot Jupiter transiting a slightly evolved G-star with a 9.48-day orbital period. This is the first planet to be confirmed from analysis of only ... More
Structure and dynamics of H$_2^+$ near the dissociation threshold: a combined experimental and computational investigationJun 16 2016The pulsed-field-ionization zero-kinetic-energy photoelectron spectrum of H$_2$ has been recorded in the vicinity of the dissociative-ionization threshold following three-photon excitation via selected rotational levels of the B $^1\Sigma_u^+$ ($v=19$) ... More
A Flexible Galerkin Scheme for Option Pricing in Lévy ModelsMar 27 2016One popular approach to option pricing in L\'evy models is through solving the related partial integro differential equation (PIDE). For the numerical solution of such equations powerful Galerkin methods have been put forward e.g. by Hilber et al. (2013). ... More
Rate-Distortion Theory of Finite Point ProcessesApr 19 2017May 22 2018We study the compression of data in the case where the useful information is contained in a set rather than a vector, i.e., the ordering of the data points is irrelevant and the number of data points is unknown. Our analysis is based on rate-distortion ... More
Simultaneous Single-Step One-Shot Optimization with Unsteady PDEsMar 03 2015Jun 23 2015The single-step one-shot method has proven to be very efficient for PDE-constrained optimization where the partial differential equation (PDE) is solved by an iterative fixed point solver. In this approach, the simulation and optimization tasks are performed ... More
A non-symmetric coupling of the finite volume method and the boundary element methodSep 01 2015As model problem we consider the prototype for flow and transport of a concentration in porous media in an interior domain and couple it with a diffusion process in the corresponding unbounded exterior domain. To solve the problem we develop a new non-symmetric ... More
Directly decomposable ideals and congruence kernels of commutative semiringsJan 17 2019As pointed out in the monographs by J. S. Golan and by W. Kuich and A. Salomaa on semirings, ideals play an important role despite the fact that they need not be congruence kernels as in the case of rings. Hence, having two commutative semirings S1 and ... More
Ideals of direct products of ringsJan 18 2019It is known that an ideal of a direct product of commutative unitary rings is directly decomposable into ideals of the corresponding factors. We show that this does not hold in general for commutative rings and we find necessary and sufficient conditions ... More
Generalized solutions for the Euler-Bernoulli model with Zener viscoelastic foundations and distributional forcesFeb 10 2011We study the initial-boundary value problem for an Euler-Bernoulli beam model with discontinuous bending stiffness laying on a viscoelastic foundation and subjected to an axial force and an external load both of Dirac-type. The corresponding model equation ... More
A Multi-step Scheme based on Cubic Spline for solving Backward Stochastic Differential EquationsSep 02 2018In this work we study a multi-step scheme on time-space grids proposed by W. Zhao et al. [28] for solving backward stochastic differential equations, where Lagrange interpolating polynomials are used to approximate the time-integrands with given values ... More
Well-Posedness of a Navier-Stokes/Mean Curvature Flow systemMay 30 2017We consider a two-phase flow of two incompressible, viscous and immiscible fluids which are separated by a sharp interface in the case of a simple phase transition. In this model the interface is no longer material and its evolution is governed by a convective ... More
Dynamical phase transition for a quantum particle sourceAug 20 2009Dec 20 2009We analyze the time evolution describing a quantum source for noninteracting particles, either bosons or fermions. The growth behaviour of the particle number (trace of the density matrix) is investigated, leading to spectral criteria for sublinear or ... More
Observation and calculation of the quasi-bound rovibrational levels of the electronic ground state of H$_2^+$Jan 13 2017Although the existence of quasi-bound rotational levels of the $X^+ \ ^2\Sigma_g^+$ ground state of H$_2^+$ has been predicted a long time ago, these states have never been observed. Calculated positions and widths of quasi-bound rotational levels located ... More
Multiplication and Composition in Weighted Modulation SpacesJan 31 2016We study the existence of the product of two weighted modulation spaces. For this purpose we discuss two different strategies. The more simple one allows transparent proofs in various situations. However, our second method allows a closer look onto associated ... More
Entropic repulsion for the Gaussian free field conditioned on disconnection by level-setsAug 29 2018We investigate level-set percolation of the discrete Gaussian free field on $\mathbb{Z}^d$, $d\geq 3$, in the strongly percolative regime. We consider the event that the level-set of the Gaussian free field below a level $\alpha$ disconnects the discrete ... More
The shear-Hall instability in newborn neutron starsOct 18 2011Aims. In the first few minutes of a newborn neutron star's life the Hall effect and differential rotation may both be important. We demonstrate that these two ingredients are sufficient for generating a 'shear-Hall instability' and for studying its excitation ... More
A generalized Schur complement for non-negative operators on linear spaceAug 04 2017Extending the corresponding notion for matrices or bounded linear operators on a Hilbert space we define a generalized Schur complement for a non-negative linear operator mapping a linear space into its dual and derive some of its properties.
Scattered slice SHARD reconstruction for motion correction in multi-shell diffusion MRI of the neonatal brainMay 08 2019Diffusion MRI offers a unique probe into neural microstructure and connectivity in the developing brain. However, analysis of neonatal brain imaging data is complicated by inevitable subject motion, leading to a series of scattered slices that need to ... More
On Lossless Causal Compression of Periodic SignalsDec 06 2018We present and study a scheme for lossless causal compression of periodic real-valued signals. In particular, our technique compresses a vector-valued signal to a scalar-valued signal by mixing it with another periodic signal. The conditions for being ... More
Solidification of porous interfaces and disconnectionJun 22 2017Feb 02 2018In this article we obtain uniform estimates on the absorption of Brownian motion by porous interfaces surrounding a compact set. An important ingredient is the construction of certain resonance sets, which are hard to avoid for Brownian motion starting ... More
Statistical mechanics of phase-space partitioning in large-scale spiking neuron circuitsMar 15 2017May 01 2017Synaptic interactions structure the phase space of the dynamics of neural circuits and constrain neural computation. Understanding how requires methods that handle those discrete interactions, yet few exist. Recently, it was discovered that even random ... More
Chebyshev Interpolation for Parametric Option PricingMay 18 2015Jul 08 2016Recurrent tasks such as pricing, calibration and risk assessment need to be executed accurately and in real-time. Simultaneously we observe an increase in model sophistication on the one hand and growing demands on the quality of risk management on the ... More
Dynamical pattern formation upon dewettingJun 16 2001Dewetting of thin liquid films is monitored in situ by atomic force microscopy, results are compared with simulations. The experimental setting is mimicked as close as possible using the experimental parameters including the effective interface potential. ... More
Fusion of Monocular Vision and Radio-based Ranging for Global Scale Estimation and Drift MitigationOct 02 2018Monocular vision-based Simultaneous Localization and Mapping (SLAM) is used for various purposes due to its advantages in cost, simple setup, as well as availability in the environments where navigation with satellites is not effective. However, camera ... More
The dimming of RW Auriga. Is dust accretion preceding an outburst?Oct 15 2018Jan 08 2019RW Aur A has experienced various dimming events in the last years, decreasing its brightness by $\sim 2\ \textrm{mag}$ for periods of months to years. Multiple observations indicate that a high concentration of dust grains, from the protoplanetary disk's ... More
Deep Learning of truncated singular values for limited view photoacoustic tomographyJan 19 2019We develop a data-driven regularization method for the severely ill-posed problem of photoacoustic image reconstruction from limited view data. Our approach is based on the regularizing networks that have been recently introduced and analyzed in [J. Schwab, ... More
An Optimization Approach to the Ordering Phase of an Attended Home Delivery ServiceMay 01 2018Nov 28 2018Attended Home Delivery (AHD) systems are used whenever a supplying company offers online shopping services that require that customers must be present when their deliveries arrive. Therefore, the supplying company and the customer must both agree on a ... More
Stability and instability of hydromagnetic Taylor-Couette flowsMar 29 2017Apr 05 2018Decades ago S. Lundquist, S. Chandrasekhar, P.H. Roberts and R. J.~Tayler first posed questions about the stability of Taylor-Couette flows of conducting material under the influence of large-scale magnetic fields. These and many new questions can now ... More
Quasiparticle Corrections to the Electronic Properties of Anion Vacancies at GaAs(110) and InP(110)Nov 27 2006We propose a new method for calculating optical defect levels and thermodynamic charge-transition levels of point defects in semiconductors, which includes quasiparticle corrections to the Kohn-Sham eigenvalues of density-functional theory. Its applicability ... More
Toward Open-Set Face RecognitionMay 03 2017May 19 2017Much research has been conducted on both face identification and face verification, with greater focus on the latter. Research on face identification has mostly focused on using closed-set protocols, which assume that all probe images used in evaluation ... More
Orbital Fingerprint of Topological Fermi Arcs in a Weyl SemimetalMar 11 2018Weyl semimetals are characterized by Fermi arc surface states. As a function of surface momentum, such arcs constitute energy-degenerate line trajectories terminating at the surface projection of two bulk Weyl nodes with opposite chirality. At these projection ... More
On the Casimir scaling violation in the cusp anomalous dimension at small angleAug 03 2017Oct 16 2017We compute the four-loop $n_f$ contribution proportional to the quartic Casimir of the QCD cusp anomalous dimension as an expansion for small cusp angle $\phi$. This piece is gauge invariant, violates Casimir scaling, and first appears at four loops. ... More
Two-Loop Massive Quark Jet Functions in SCETApr 29 2019We calculate the $\mathcal O(\alpha_s^2)$ corrections to the primary massive quark jet functions in Soft-Collinear Effective Theory (SCET). They are an important ingredient in factorized predictions for inclusive jet mass cross sections initiated by massive ... More
Strong photon coupling to the quadrupole moment of an electron in solid stateMay 02 2019The implementation of circuit quantum electrodynamics allows coupling distant qubits by microwave photons hosted in on-chip superconducting resonators. Typically, the qubit-photon interaction is realized by coupling the photons to the electric dipole ... More
Occupation times of sets of infinite measure for ergodic transformationsJun 28 2004Assume that $T$ is a conservative ergodic measure preserving transformation of the infinite measure space $(X,\mathcal{A},\mu)$.We study the asymptotic behaviour of occupation times of certain subsets of infinite measure. Specifically, we prove a Darling-Kac ... More
Tangles are decided by weighted vertex setsNov 16 2018Feb 19 2019We show that, given a $ k $-tangle $ \tau $ in a graph $ G $, there always exists a weight function $ w: V(G)\to\mathbb{N} $ such that a separation $ (A,B) $ of $ G $ of order $ <k $ lies in $ \tau $ if and only if $ w(A)<w(B) $, where $ w(U):=\sum_{u\in ... More
Affine HJM Framework on $S_{d}^{+}$ and Long-Term YieldNov 04 2013Aug 21 2015We develop the HJM framework for forward rates driven by affine processes on the state space of symmetric positive matrices. In this setting we find a representation for the long-term yield and investigate the yield's asymptotic behaviour.
Aligator.jl - A Julia Package for Loop Invariant GenerationAug 16 2018We describe the Aligator.jl software package for automatically generating all polynomial invariants of the rich class of extended P-solvable loops with nested conditionals. Aligator.jl is written in the programming language Julia and is open-source. Aligator.jl ... More
Derivation of the Time Dependent Gross-Pitaevskii Equation in Two DimensionsAug 18 2016Sep 21 2018We present a microscopic derivation of the defocusing two-dimensional cubic nonlinear Schr\"odinger equation as a mean field equation starting from an interacting $N$-particle system of Bosons. We consider the interaction potential to be given either ... More
Discretized Fast-Slow Systems near Pitchfork SingularitiesFeb 18 2019Motivated by the normal form of a fast-slow ordinary differential equation exhibiting a pitchfork singularity we consider the discrete-time dynamical system that is obtained by an application of the explicit Euler method. Tracking trajectories in the ... More
Progressive Simplification of Polygonal CurvesJun 07 2018Simplifying polygonal curves at different levels of detail is an important problem with many applications. Existing geometric optimization algorithms are only capable of minimizing the complexity of a simplified curve for a single level of detail. We ... More
Probabilistic Trajectory Segmentation by Means of Hierarchical Dirichlet Process Switching Linear Dynamical SystemsMay 29 2018Aug 07 2018Using movement primitive libraries is an effective means to enable robots to solve more complex tasks. In order to build these movement libraries, current algorithms require a prior segmentation of the demonstration trajectories. A promising approach ... More
A review of our current knowledge of clouded leopards (Neofelis nebulosa)Dec 12 2017Little is known about clouded leopards (Neofelis nebulosa), who have a vulnerable population that extends across southern Asia. We reviewed the literature and synthesized what is known about their ecology and behavior. Much of the published literature ... More
Nmag micromagnetic simulation tool - software engineering lessons learnedJan 27 2016Feb 28 2016We review design and development decisions and their impact for the open source code Nmag from a software engineering in computational science point of view. We summarise lessons learned and recommendations for future computational science projects. Key ... More
A Relaxed Kačanov Iteration for the $p$-Poisson ProblemFeb 13 2017In this paper, we introduce an iterative linearization scheme that allows to approximate the weak solution of the $p$-Poisson problem \begin{align*} -\operatorname{div}(|\nabla u|^{p-2}\nabla u) &= f\quad\text{in }\Omega, u&= 0\quad\text{on}\partial\Omega ... More
Decremental Strongly-Connected Components and Single-Source Reachability in Near-Linear TimeJan 11 2019Mar 14 2019Computing the Strongly-Connected Components (SCCs) in a graph $G=(V,E)$ is known to take only $O(m + n)$ time using an algorithm by Tarjan from 1972[SICOMP 72] where $m = |E|$, $n=|V|$. For fully-dynamic graphs, conditional lower bounds provide evidence ... More
Automated Generation of Non-Linear Loop Invariants Utilizing Hypergeometric SequencesMay 08 2017May 11 2017Analyzing and reasoning about safety properties of software systems becomes an especially challenging task for programs with complex flow and, in particular, with loops or recursion. For such programs one needs additional information, for example in the ... More
Underactuated Hand Design Using Mechanically Realizable ManifoldsMar 26 2018Aug 01 2018Hand synergies, or joint coordination patterns, have become an effective tool for achieving versatile robotic grasping with simple hands or planning algorithms. Here we propose a method to determine the hand synergies such that they can be physically ... More
The Long-Term Swap Rate and a General Analysis of Long-Term Interest RatesJul 01 2015Oct 16 2016We introduce here for the first time the long-term swap rate, characterised as the fair rate of an overnight indexed swap with infinitely many exchanges. Furthermore we analyse the relationship between the long-term swap rate, the long-term yield, see ... More
B $\rightarrow f_2(1270)$ form factors with light-cone sum rulesApr 09 2018We construct the quark-antiquark chiral odd distribution amplitudes including twist-four mass contributions for tensor mesons. We also give quark-antiquark-gluon distribution amplitudes, where we calculate the input parameters with QCD sum rules. With ... More
The Three-loop Quark Jet FunctionApr 25 2018Sep 18 2018We calculate the massless quark jet function to three-loop order. The quark jet function is a universal ingredient in SCET factorization for many collider and decay processes with quark initiated final state jets. Our three-loop result contributes to ... More
Non-equilibrium quantum transport coefficients and the transient dynamics of full counting statistics in the strong coupling and non-Markovian regimesJun 16 2016Dec 20 2016Non-equilibrium transport properties of quantum systems have recently become experimentally accessible in a number of platforms in so-called full-counting experiments that measure transient and steady state non-equilibrium transport dynamics. We show ... More
Sidon set systemsFeb 28 2018Sep 07 2018A family ${\mathcal A}$ of $k$-subsets of $\{1,2,\dots, N\}$ is a Sidon system if the sumsets $A+B$, $A,B\in \mathcal{A}$ are pairwise distinct. We show that the largest cardinality $F_k(N)$ of a Sidon system of $k$-subsets of $[N]$ satisfies $F_k(N)\le ... More
On the integrality of Seshadri constants of abelian surfacesMay 14 2018In this paper we consider the question of when Seshadri constants on abelian surfaces are integers. Our first result concerns self-products $E\times E$ of elliptic curves: If $E$ has complex multiplication in $\Z[i]$ or in $\Z[\frac12(1+i\sqrt3)]$ or ... More
Uniqueness of the Representation in Homogeneous Isotropic LQCSep 12 2016Mar 28 2018We show that the standard representation of homogeneous isotropic loop quantum cosmology (LQC) is the GNS-representation that corresponds to the unique state on the reduced quantum holonomy-flux $^*$-algebra that is invariant under residual diffeomorphisms ... More
Linear programming based approximation for unweighted induced matchings --- breaking the $Δ$ barrierDec 14 2018A matching in a graph is induced if no two of its edges are joined by an edge, and finding a large induced matching is a very hard problem. Lin et al. (Approximating weighted induced matchings, Discrete Applied Mathematics 243 (2018) 304-310) provide ... More
Stellar Flares from the First Tess Data Release: Exploring a New Sample of M-dwarfsJan 02 2019We perform a study of stellar flares for the 24,809 stars observed with 2 minute cadence during the first two months of the TESS mission. Flares may erode exoplanets' atmospheres and impact their habitability, but might also trigger the genesis of life ... More
Second-order correlations in single-particle interferometryMar 22 2017Interferometers with single particles are susceptible for dephasing perturbations from the environment, such as electromagnetic oscillations or mechanical vibrations. On the one hand, this limits sensitive quantum phase measurements as it reduces the ... More
Combinatorial Gradient Fields for 2D Images with Empirically Convergent SeparatricesAug 31 2012This paper proposes an efficient probabilistic method that computes combinatorial gradient fields for two dimensional image data. In contrast to existing algorithms, this approach yields a geometric Morse-Smale complex that converges almost surely to ... More
Variance-based Robust Optimization of a Permanent Magnet Synchronous MachineSep 08 2017This paper focuses on the application of the variance-based global sensitivity analysis for a topology derivative method in order to solve a stochastic nonlinear time-dependent magnetoquasistatic interface problem. To illustrate the approach a permanent ... More
The Influence of Differential Privacy on Short Term Electric Load ForecastingJul 06 2018There has been a large number of contributions on privacy-preserving smart metering with Differential Privacy, addressing questions from actual enforcement at the smart meter to billing at the energy provider. However, exploitation is mostly limited to ... More
Surveyor Gender Modifies Average Survey Responses: Evidence from Household Surveys in Four Sub-Saharan African CountriesOct 03 2018Relatively little is known regarding the influence of surveyor traits on respondent behavior. In this paper, we assess the extent to which survey gender modifies average survey responses in the context of health-focused household surveys. We pool data ... More
Friend Inspector: A Serious Game to Enhance Privacy Awareness in Social NetworksFeb 20 2014Currently, many users of Social Network Sites are insufficiently aware of who can see their shared personal items. Nonetheless, most approaches focus on enhancing privacy in Social Networks through improved privacy settings, neglecting the fact that privacy ... More
TESS full orbital phase curve of the WASP-18b systemNov 14 2018Mar 15 2019We present a visible-light full orbital phase curve of the transiting planet WASP-18b measured by the TESS Mission. The phase curve includes the transit, secondary eclipse, and sinusoidal modulations across the orbital phase shaped by the planet's atmospheric ... More
The QCD phase diagram from analytic continuationJul 27 2015Nov 12 2015We present the crossover line between the quark gluon plasma and the hadron gas phases for small real chemical potentials. First we determine the effect of imaginary values of the chemical potential on the transition temperature using lattice QCD simulations. ... More
Automatic vetting of planet candidates from ground based surveys: Machine learning with NGTSMay 18 2018State of the art exoplanet transit surveys are producing ever increasing quantities of data. To make the best use of this resource, in detecting interesting planetary systems or in determining accurate planetary population statistics, requires new automated ... More
Ground-based detection of G star superflares with NGTSApr 10 2018We present high cadence detections of two superflares from a bright G8 star (V = 11.56) with the Next Generation Transit Survey (NGTS). We improve upon previous superflare detections by resolving the flare rise and peak, allowing us to fit a solar flare ... More
Redefining Ultrasound Compounding: Computational SonographyNov 05 2018Freehand three-dimensional ultrasound (3D-US) has gained considerable interest in research, but even today suffers from its high inter-operator variability in clinical practice. The high variability mainly arises from tracking inaccuracies as well as ... More
Detection of a giant flare displaying quasi-periodic pulsations from a pre-main sequence M star with NGTSNov 05 2018We present the detection of an energetic flare on the pre-main sequence M3 star NGTS J121939.5-355557, which we estimate as only 2 Myr old. The flare had an energy of $3.2\pm^{0.4}_{0.3}\times 10^{36}$erg and a fractional amplitude of $7.2\pm0.8$, making ... More
Heterotic Bundles on Calabi-Yau Manifolds with Small Picard NumberAug 04 2011We undertake a systematic scan of vector bundles over spaces from the largest database of known Calabi-Yau three-folds, in the context of heterotic string compactification. Specifically, we construct positive rank five monad bundles over Calabi-Yau hypersurfaces ... More
Statistical mechanics approach to the electric polarization and dielectric constant of band insulatorsMay 10 2016Jan 31 2017We develop a theory for the analytic computation of the free energy of band insulators in the presence of a uniform and constant electric field. The two key ingredients are a perturbation-like expression of the Wannier-Stark energy spectrum of electrons ... More
The Conformal Einstein Field Equations with Massless Vlasov MatterMar 28 2019We prove the stability of de Sitter space-time as a solution to the Einstein-Vlasov system with massless particles. The semi-global stability of Minkowski space-time is also addressed. The proof relies on conformal techniques, namely Friedrich's conformal ... More
Solving Vertex Cover in Polynomial Time on Hyperbolic Random GraphsApr 29 2019The VertexCover problem is proven to be computationally hard in different ways: It is NP-complete to find an optimal solution and even NP-hard to find an approximation with reasonable factors. In contrast, recent experiments suggest that on many real-world ... More
The influence of metallicity on stellar differential rotation and magnetic activityNov 21 2017Observations of Sun-like stars over the last half-century have improved our understanding of how magnetic dynamos, like that responsible for the 11-year solar cycle, change with rotation, mass and age. Here we show for the first time how metallicity can ... More
Constraints on Compound Chondrule Formation from Laboratory High-Temperature CollisionsNov 07 2018In laboratory experiments, spherical 1 mm-wide glass and basalt particles are heated, and the hot particles collide at about 1m/s with a flat glass target that is at room temperature. When the particles are heated below 900 K, the collisions are essentially ... More
Exploiting Map Topology Knowledge for Context-predictive Multi-interface Car-to-cloud CommunicationJul 03 2018While the automotive industry is currently facing a contest among different communication technologies and paradigms about predominance in the connected vehicles sector, the diversity of the various application requirements makes it unlikely that a single ... More