Results for "Martin Fuchs"

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Existence results for generalized EED denoising problemsSep 18 2019The joint work of the authors with Marcelo C\'ardenas and Joachim Weickert \cite{BCFW:2019_1} on edge-enhancing diffusion inpainting problems leads to the analysis of related denoising problems. Here, a surprisingly broad class of diffusion tensors is ... More
A Liouville theorem for stationary incompressible fluids of von Mises typeMay 22 2018We consider entire solutions $u$ of the equations describing the stationary flow of a generalized Newtonian fluid in 2D concentrating on the question, if a Liouville-type result holds in the sense that the boundedness of $u$ implies its constancy. A positive ... More
Liouville-type theorems for steady flows of degenerate power law fluids in the planeOct 15 2012We extend the Liouville-type theorems of Gilbarg and Weinberger and of Koch, Nadirashvili, Seregin and Sver\'ak valid for the stationary variant of the classical Navier-Stokes equations in 2D to the degenerate power law fluid model.
Ab initio pseudopotentials for electronic structure calculations of poly-atomic systems using density-functional theoryJul 31 1998The package fhi98PP allows one to generate norm-conserving pseudopotentials adapted to density-functional theory total-energy calculations for a multitude of elements throughout the periodic table, including first-row and transition metal elements. The ... More
A remark on the denoising of greyscale images using energy densities with varying growth ratesMar 28 2018We prove the solvability in Sobolev spaces for a class of variational problems related to the TV-model proposed by Rudin, Osher and Fatemi in [1] for the denoising of greyscale images. In contrast to their approach we discuss energy densities with variable ... More
A higher order TV-type variational problem related to the denoising and inpainting of imagesMar 27 2018We give a comprehensive survey on a class of higher order variational problems which are motivated by applications in mathematical imaging. The overall aim of this note is to investigate if and in which manner results from the first author's previous ... More
Neutron Resonance Spin Flippers: Static Coils Manufactured by Electrical Discharge MachiningApr 14 2014Jul 11 2014Radiofrequency spin flippers (RFSF) are key elements of Neutron Resonance Spin Echo (NRSE) spectrometers, which allow performing controlled manipulations of the beam polarization. We report on the design and test of a new type of RFSF which originality ... More
Darboux and Calapso transforms of meromorphically isothermic surfacesJan 17 2019We consider those simply connected isothermic surfaces for which their Hopf differential factorizes into a real function and a meromorphic quadratic differential that has a zero or pole at some point, but is nowhere zero and holomorphic otherwise. Upon ... More
Assessment of cortical reorganization and preserved function in phantom limb pain: a methodological perspectiveFeb 19 2019Mar 05 2019Phantom limb pain (PLP) has been associated with both the reorganization of the somatotopic map in primary somatosensory cortex (S1) and preserved S1 function. Here we assessed the nature of the information (sensory, motor) that reaches S1 and methodological ... More
A reciprocity principle for constrained isoperimetric problems and existence of isoperimetric subregions in convex setsMar 28 2018It is a well known fact that in $\mathbb{R}^n$ a subset of minimal perimeter $L$ among all sets of a given volume is also a set of maximal volume among all sets of the same perimeter $L$. This is called the reciprocity principle for isoperimetric problems. ... More
Signal recovery via TV-type energiesMar 28 2018We consider one-dimensional variants of the classical first order total variation denoising model introduced by Rudin, Osher and Fatemi. This study is based on our previous work on various denoising and inpainting problems in image analysis, where we ... More
Noise recovery for Lévy-driven CARMA processes and high-frequency behaviour of approximating Riemann sumsOct 04 2012Jan 31 2013We consider high-frequency sampled continuous-time autoregressive moving average (CARMA) models driven by finite-variance zero-mean L\'evy processes. An L^2-consistent estimator for the increments of the driving L\'evy process without order selection ... More
Weighing stellar - mass black holes with GaiaOct 21 2004Oct 28 2004Stellar-mass black holes have been detected by radial-velocity observations in star/black hole binaries. These allow only the determination of the mass function. Tracking the astrometric orbits of the visible components of the star/black hole binaries ... More
Simplex Stochastic Collocation for Piecewise Smooth Functions with KinksFeb 18 2019Most approximation methods in high dimensions exploit smoothness of the function being approximated. These methods provide poor convergence results for non-smooth functions with kinks. For example, such kinks can arise in the uncertainty quantification ... More
$t$-perfection in near-bipartite and in $P_5$-free graphsJul 01 2015A graph is called $t$-perfect if its stable set polytope is fully described by non-negativity, edge and odd-cycle constraints. We characterise near-bipartite $t$-perfect and $P_5$-free $t$-perfect graphs in terms of forbidden $t$-minors. Moreover, we ... More
30 years of collaborationNov 24 2015We highlight some of the most important cornerstones of the long standing and very fruitful collaboration of the Austrian Diophantine Number Theory research group and the Number Theory and Cryptography School of Debrecen. However, we do not plan to be ... More
Reducing quadrangulations of the sphere and the projective planeJun 24 2016Mar 13 2017We show that every quadrangulation of the sphere can be transformed into a $4$-cycle by deletions of degree-$2$ vertices and by $t$-contractions at degree-$3$ vertices. A $t$-contraction simultaneously contracts all incident edges at a vertex with stable ... More
Full Logarithmic Conformal Field theory - an Attempt at a Status ReportMar 07 2019Logarithmic conformal field theories are based on vertex algebras with non-semisimple representation categories. While examples of such theories have been known for more than 25 years, some crucial aspects of local logarithmic CFTs have been understood ... More
Spectral Representation of Multivariate Regularly Varying Lévy and CARMA processesMay 13 2011A spectral representation for regularly varying L\'evy processes with index between one and two is established and the properties of the resulting random noise are discussed in detail giving also new insight in the $L^2$-case where the noise is a random ... More
Category theory for conformal boundary conditionsJun 07 2001Aug 04 2006We study properties of the category of modules of an algebra object A in a tensor category C. We show that the module category inherits various structures from C, provided that A is a Frobenius algebra with certain additional properties. As a by-product ... More
Estimators for a Class of Bivariate Measures of Concordance for CopulasJan 17 2017In the present paper we propose and study estimators for a wide class of bivariate measures of concordance for copulas. These measures of concordance are generated by a copula and generalize Spearman's rho and Gini's gamma. In the case of Spearman's rho ... More
Pseudopotential study of binding properties of solids within generalized gradient approximations: The role of core-valence exchange-correlationJul 23 1997In ab initio pseudopotential calculations within density-functional theory the nonlinear exchange-correlation interaction between valence and core electrons is often treated linearly through the pseudopotential. We discuss the accuracy and limitations ... More
Changing the Heights of Automorphism Towers by Forcing with Souslin Trees over LFeb 26 2007We prove that there are groups in the constructible universe whose automorphism towers are highly malleable by forcing. This is a consequence of the fact that, under a suitable diamond hypothesis, there are sufficiently many highly rigid non-isomorphic ... More
Existence Theory for the EED Inpainting ProblemJun 11 2019We establish an existence theory for an elliptic boundary value problem in image analysis known as edge-enhancing diffusion (EED) inpainting. The EED inpainting problem aims at restoring missing data in an image as steady state of a nonlinear anisotropic ... More
On Kendall's Tau for Order StatisticsAug 03 2018Every copula $ C $ for a random vector $ {\bf X}=(X_1,\dots,X_d) $ with identically distributed coordinates determines a unique copula $ C_{:d} $ for its order statistic $ {\bf X}_{:d}=(X_{1:d},\dots,X_{d:d}) $. In the present paper we study the dependence ... More
On the local boundedness of generalized minimizers of variational problems with linear growthApr 04 2018We prove local boundedness of generalized solutions to a large class of variational problems of linear growth including boundary value problems of minimal surface type and models from image analysis related to the procedure of TV-regularization occurring ... More
Static Properties of a Simulated Supercooled Polymer Melt: Structure Factors, Monomer Distributions Relative to the Center of Mass, and Triple Correlation FunctionsFeb 25 2004We analyze structural and conformational properties in a simulated bead-spring model of a non-entangled, supercooled polymer melt. We explore the statics of the model via various structure factors, involving not only the monomers, but also the center ... More
Convex Regularization of Multi-Channel Images Based on Variants of the TV-ModelApr 04 2018We discuss existence and regularity results for multi-channel images in the setting of isotropic and anisotropic variants of the TV-model.
On the solvability in Sobolev spaces and related regularity results for a variant of the TV-image recovery model: the vector-valued caseMar 27 2018We study classes of variational problems with energy densities of linear growth acting on vector-valued functions. Our energies are strictly convex variants of the TV-regularization model introduced by Rudin, Osher and Fatemi [15] as a powerful tool in ... More
On Quantile Risk Measures and Their DomainJul 21 2017In the present paper we study quantile risk measures and their domain. Our starting point is that, for a probability measure $ Q $ on the open unit interval and a wide class $ \mathcal{L}_Q $ of random variables, we define the quantile risk measure $ ... More
Stationarity and Geometric Ergodicity of BEKK Multivariate GARCH ModelsJun 01 2011Conditions for the existence of strictly stationary multivariate GARCH processes in the so-called BEKK parametrisation, which is the most general form of multivariate GARCH processes typically used in applications, and for their geometric ergodicity are ... More
Superconformal Blocks for Mixed 1/2-BPS Correlators with $SU(2)$ R-symmetryAug 07 2019For SCFTs with an $SU(2)$ R-symmetry, we determine the superconformal blocks that contribute to the four-point correlation function of a priori distinct half-BPS superconformal primaries as an expansion in terms of the relevant bosonic conformal blocks. ... More
Markov chain analysis of random walks on disordered mediumNov 12 1993We study the dynamical exponents $d_{w}$ and $d_{s}$ for a particle diffusing in a disordered medium (modeled by a percolation cluster), from the regime of extreme disorder (i.e., when the percolation cluster is a fractal at $p=p_{c}$) to the Lorentz ... More
Density waves in the shearing sheet V. Feedback cycle for swing amplification by non-linear effectsAug 18 2005Non-linear effects in the dynamical evolution of a shearing sheet made of stars are studied. First the implications of hitherto neglected non-linearities of the Boltzmann equation for the dynamical evolution of the shearing sheet are investigated. Using ... More
Twining characters and Picard groups in rational conformal field theoryFeb 05 2006Picard groups of tensor categories play an important role in rational conformal field theory. The Picard group of the representation category C of a rational vertex algebra can be used to construct examples of (symmetric special) Frobenius algebras in ... More
Set-Theoretic GeologyJul 24 2011Nov 18 2014A ground of the universe V is a transitive proper class W subset V, such that W is a model of ZFC and V is obtained by set forcing over W, so that V = W[G] for some W-generic filter G subset P in W . The model V satisfies the ground axiom GA if there ... More
From coin-tossing to rock-paper-scissors and beyond: A log-exp gap theorem for selecting a leaderJul 29 2015Jul 30 2015A class of games for finding a leader among a group of candidates is studied in detail. This class covers games based on coin-tossing and rock-paper-scissors as special cases and its complexity exhibits similar stochastic behaviors: either of logarithmic ... More
Cooperation between Top-Down and Bottom-Up Theorem ProversMay 27 2011Top-down and bottom-up theorem proving approaches each have specific advantages and disadvantages. Bottom-up provers profit from strong redundancy control but suffer from the lack of goal-orientation, whereas top-down provers are goal-oriented but often ... More
Time delays from one-photon transitions in the continuumJul 08 2019Attosecond photoionisation time delays reveal information about the potential energy landscape an outgoing electron wavepacket probes upon ionisation. In this study we experimentally quantify, for the first time, the dependence of the time delay on the ... More
On the accuracy of DFT exchange-correlation functionals for H bonds in small water clusters II: The water hexamer and van der Waals interactionsAug 22 2008Second order Moeller-Plesset perturbation theory (MP2) at the complete basis set (CBS) limit and diffusion quantum Monte Carlo (DMC) are used to examine several low energy isomers of the water hexamer. Both approaches predict the so-called "prism" to ... More
On the Limitations of Representing Functions on SetsJan 25 2019Recent work on the representation of functions on sets has considered the use of summation in a latent space to enforce permutation invariance. In particular, it has been conjectured that the dimension of this latent space may remain fixed as the cardinality ... More
Installing, Running and Maintaining Large Linux Clusters at CERNJun 12 2003Having built up Linux clusters to more than 1000 nodes over the past five years, we already have practical experience confronting some of the LHC scale computing challenges: scalability, automation, hardware diversity, security, and rolling OS upgrades. ... More
Structural and conformational dynamics of supercooled polymer melts: Insights from first-principles theory and simulationsDec 05 2007We report on quantitative comparisons between simulation results of a bead-spring model and mode-coupling theory calculations for the structural and conformational dynamics of a supercooled, unentangled polymer melt. We find semiquantitative agreement ... More
Breaking the Barriers to True Augmented RealityDec 17 2015In recent years, Augmented Reality (AR) and Virtual Reality (VR) have gained considerable commercial traction, with Facebook acquiring Oculus VR for \$2 billion, Magic Leap attracting more than \$500 million of funding, and Microsoft announcing their ... More
Universal simple current vertex operatorsFeb 27 1997We construct a vertex operator realization for the simple current primary fields of WZW theories which are based on simply laced affine Lie algebras g. This is achieved by employing an embedding of the integrable highest weight modules of g into the Fock ... More
THE SINGULARITY STRUCTURE OF THE YANG-MILLS CONFIGURATION SPACEJun 01 1995The geometric description of Yang-Mills theories and their configuration space M is reviewed. The presence of singularities in M is explained and some of their properties are described. The singularity structure is analyzed in detail for structure group ... More
Density waves in the shearing sheet IV. Interaction with a live dark haloMar 01 2004It is shown that if the self-gravitating shearing sheet, a model of a patch of a galactic disk, is embedded in a live dark halo, this has a strong effect on the dynamics of density waves in the sheet. I describe how the density waves and the halo interact ... More
Massive Disks in Low Surface Brightness GalaxiesSep 09 2002An update of the set of low surface brightness galaxies is presented which can be used to set constraints on the otherwise ambiguous decompositions of their rotation curves into contributions due to the various components of the galaxies. The selected ... More
The Amount of Dark Matter in Spiral GalaxiesOct 18 2000Nov 30 2000The `maximum' disk hypothesis of galactic disks imbedded in dark matter halos is examined. First, decompositions of the rotation curves of NGC 2613, 3198, 6503, and 7184 are analyzed. For these galaxies the radial velocity dispersions of the stars have ... More
Recent progress constraining the nuclear equation of state from astrophysics and heavy ion reactionsJun 01 2007The quest for the nuclear equation of state (EoS) at high densities and/or extreme isospin is one of the longstanding problems of nuclear physics. Ab initio calculations for the nuclear many-body problem make predictions for the density and isospin dependence ... More
Geometric orbital susceptibility: quantum metric without Berry curvatureMay 04 2016Oct 21 2016The orbital magnetic susceptibility of an electron gas in a periodic potential depends not only on the zero field energy spectrum but also on the geometric structure of cell-periodic Bloch states which encodes interband effects. In addition to the Berry ... More
The U(1)s in the Finite N Limit of Orbifold Field TheoriesMar 26 2000Jul 31 2000We study theories generated by orbifolding the {\cal N}=4 super conformal U(N) Yang Mills theory with finite N, focusing on the r\^ole of the remnant U(1) gauge symmetries of the orbifold process. It is well known that the one loop beta functions of the ... More
The SIC Question: History and State of PlayMar 23 2017Jul 11 2017Recent years have seen significant advances in the study of symmetric informationally complete (SIC) quantum measurements, also known as maximal sets of complex equiangular lines. Previously, the published record contained solutions up to dimension 67, ... More
The Quantum Symmetry of Rational Field TheoriesDec 03 1993The quantum symmetry of a rational quantum field theory is a finite- dimensional multi-matrix algebra. Its representation category, which determines the fusion rules and braid group representations of superselection sectors, is a braided monoidal C^*-category. ... More
Nonlinear rheological properties of dense colloidal dispersions close to a glass transition under steady shearOct 14 2008The nonlinear rheological properties of dense colloidal suspensions under steady shear are discussed within a first principles approach. It starts from the Smoluchowski equation of interacting Brownian particles in a given shear flow, derives generalized ... More
Wakes in Dark Matter HalosJan 04 2005I discuss the dynamical interaction of galactic disks with the surrounding dark matter halos. In particular it is demonstrated that if the self-gravitating shearing sheet, a model of a patch of a galactic disk, is embedded in a live dark halo, this has ... More
Dynamics of the Disks of Nearby GalaxiesOct 20 2008I describe how the dynamics of galactic disks can be inferred by imaging and spectroscopy. Next I demonstrate that the decomposition of the rotation curves of spiral galaxies into the contributions by the various components of the galaxies is highly degenerate. ... More
Multiwavelength Observation of SS433 Jet Interaction with the Interstellar MediumJul 19 2002SS433 is an X-ray binary emitting persistent relativistic double sided jets that expand into the surrounding W50 radio nebula. The SS433/W50 system is then an excellent laboratory for studying relativistic jet interaction with the surrounding interstellar ... More
Strong suppression of the Curie temperature in the electron-doped system La1-xCexCoO3Mar 29 2005We show for the system La1-xCexCoO3 (0.1 <= x <= 0.4) that it is possible to synthesize electron-doped cobaltites by the growth of epitaxial thin films. For La1-xCexCoO3, ferromagnetic order is observed within the entire doping range (with the maximum ... More
Searching for Biophysically Realistic Parameters for Dynamic Neuron Models by Genetic Algorithms from Calcium Imaging RecordingNov 04 2017Individual Neurons in the nervous systems exploit various dynamics. To capture these dynamics for single neurons, we tune the parameters of an electrophysiological model of nerve cells, to fit experimental data obtained by calcium imaging. A search for ... More
The strong Prikry propertyJul 20 2017I isolate a combinatorial property of a poset $\mathbb{P}$ that I call the strong Prikry property, which implies the existence of an ultrafilter on the complete Boolean algebra $\mathbb{B}$ of $\mathbb{P}$ such that one inclusion of the Boolean ultrapower ... More
Dependence and phase changes in random $m$-ary search treesJan 21 2015Feb 25 2016We study the joint asymptotic behavior of the space requirement and the total path length (either summing over all root-key distances or over all root-node distances) in random $m$-ary search trees. The covariance turns out to exhibit a change of asymptotic ... More
Additivity of Spin^c Quantization under CuttingAug 08 2007A G-equivariant spin^c structure on a manifold gives rise to a virtual representation of the group G, called the spin^c quantization of the manifold. We present a cutting construction for S^1-equivariant spin^c manifolds, and show that the quantization ... More
Constraints on the Decomposition of the Rotation Curves of Spiral GalaxiesDec 20 2002I discuss anew how arguments about the internal dynamics of galactic disks set constraints on the otherwise ambiguous decomposition of the rotation curves of spiral galaxies into the contributions by the various constituents of the galaxies. Analyzing ... More
Discussion of: Statistical analysis of an archeological findApr 01 2008Discussion of ``Statistical analysis of an archeological find'' by Andrey Feuerverger [arXiv:0804.0079]
The Nuclear Equation of State at high densitiesOct 10 2006Ab inito calculations for the nuclear many-body problem make predictions for the density and isospin dependence of the nuclear equation-of-state (EOS) far away from the saturation point of nuclear matter. I compare predictions from microscopic and phenomenological ... More
The Relativistic Dirac-Brueckner Approach to Nuclear MatterSep 01 2003Sep 04 2003An overview on the relativistic Dirac-Brueckner approach to the nuclear many-body problem is given. Different approximation schemes are discussed, with particular emphasis on the nuclear self-energy and the saturation mechanism of nuclear matter. I will ... More
Strangeness production in heavy ion reactions at intermediate energiesDec 15 2003Mar 05 2004Kaon production, in particular $K^+$ production in heavy ion collisions at intermediate energies is discussed. Main emphasis is put on the question if subthreshold $K^+$ production can serve as a suitable tool to test the high density phase of such reactions ... More
Equivariant K-homology of Bianchi groups with non-trivial class groupJan 06 2013May 13 2013We compute the equivariant K-homology of the groups PSL_2 of imaginary quadratic integers with trivial and non-trivial class-group. This was done before only for cases of trivial class number. We rely on reduction theory in the form of the $\Gamma$-CW-complex ... More
A Reconfigurable Chaotic Cavity with Fluorescent Lamps for Microwave Computational ImagingOct 16 2018Several computational imaging systems have recently been proposed at microwave and millimeter-wave frequencies enabling a fast and low cost reconstruction of the scattering strength of a scene. The quality of the reconstructed images is directly linked ... More
Understanding Neural Networks Through Deep VisualizationJun 22 2015Recent years have produced great advances in training large, deep neural networks (DNNs), including notable successes in training convolutional neural networks (convnets) to recognize natural images. However, our understanding of how these models work, ... More
Experimental Evaluation of Distributed Node Coloring Algorithms for Wireless NetworksNov 13 2015In this paper we evaluate distributed node coloring algorithms for wireless networks using the network simulator Sinalgo [by DCG@ETHZ]. All considered algorithms operate in the realistic signal-to-interference-and-noise-ratio (SINR) model of interference. ... More
Node Profiles of Symmetric Digital Search TreesNov 18 2017May 29 2019We give a detailed analysis in distribution of the profiles of random symmetric digital search trees, which are in close connection with the performance of the search complexity of random queries in such trees. While the expected profiles have been analyzed ... More
Spin-c Prequantization and Symplectic CuttingOct 23 2007Dec 12 2007We define spin-c prequantization of a symplectic manifold to be a spin-c structure and a connection which are compatible with the symplectic form. We describe the cutting of an S^1-equivariant spin-c prequantization. The cutting process involves a choice ... More
A Universal Property of the Groups Spin^c and Mp^cSep 15 2007It is well known that spinors on oriented Riemannian manifolds cannot be defined as sections of a vector bundle associated with the frame bundle. For this reason spin and spin^c structures are often introduced. In this paper we prove that spin^c structures ... More
Lectures on conformal field theory and Kac-Moody algebrasFeb 27 1997This is an introduction to the basic ideas and to a few further selected topics in conformal quantum field theory and in the theory of Kac-Moody algebras.
Density waves in the shearing sheet I. Swing amplificationDec 21 2000Mar 02 2001The shearing sheet model of a galactic disk is studied anew. The theoretical description of its dynamics is based on three building blocks: Stellar orbits, which are described here in epicyclic approximation, the collisionless Boltzmann equation determining ... More
NGC2613, 3198, 6503, 7184: Case studies against `maximum' disksDec 02 1998Decompositions of the rotation curves of NGC2613, 3198, 6505, and 7184 are analysed. For these galaxies the radial velocity dispersions of the stars have been measured and their morphology is clearly discernible. If the parameters of the decompositions ... More
NGC 488: Has its massive bulge been build up by minor mergers?Aug 04 1997Using recent observations of the kinematics of the disk stars the dynamical state of the disk of NGC 488 is discussed. The disk is shown to be dynamically `cool', so that NGC 488 cannot have experienced many -- even minor -- mergers in the past.
The high density equation of state: constraints from accelerators and astrophysicsNov 21 2007The nuclear equation of state (EoS) at high densities and/or extreme isospin is one of the longstanding problems of nuclear physics. In the last years substantial progress has been made to constrain the EoS both, from the astrophysical side and from accelerator ... More
Kaon production in heavy ion reactions at intermediate energiesJul 07 2005Sep 01 2005The article reviews the physics related to kaon and antikaon production in heavy ion reactions at intermediate energies. Chiral dynamics predicts substantial modifications of the kaon properties in a dense nuclear environment. The status of the theoretical ... More
Transformations and singularities of polarized curvesJul 02 2018We study the limiting behaviour of Darboux and Calapso transforms of polarized curves in the conformal n-dimensional sphere, when the polarization has a pole of first or second order at some point. We prove that for a pole of first order, as the singularity ... More
ISO's view of SS433 Jet Interactions with the Interstellar MediumDec 14 2001SS433 is a jet emitting X-ray binary surrounded by the W50 radio nebula. The SS433/W50 system is an excellent laboratory for studying relativistic jet interaction with the surrounding interstellar medium. In this context, part of the W50 nebula has been ... More
Interference effects of neutral MSSM Higgs bosons with a generalised narrow-width approximationNov 19 2014Mixing effects in the MSSM Higgs sector can give rise to a sizeable interference between the neutral Higgs bosons. On the other hand, factorising a more complicated process into production and decay parts by means of the narrow-width approximation (NWA) ... More
Relaxion and light (pseudo)scalars at the HL-LHC and lepton collidersJul 27 2018We study the potential of future lepton colliders, running at the Z-pole and above, and the High-Luminosity LHC to search for the relaxion and other light scalars $\phi$. We investigate the interplay of direct searches and precision observables for both ... More
Subcomplete forcing principles and definable well-ordersAug 28 2017Feb 13 2018It is shown that the boldface maximality principle for subcomplete forcing, together with the assumption that the universe has only set-many grounds, implies the existence of a (parameter-free) definable well-ordering of $\mathcal{P}(\omega_1)$. The same ... More
Fusion rules in conformal field theoryJun 30 1993Jul 09 1993Several aspects of fusion rings and fusion rule algebras, and of their manifestations in twodimensional (conformal) field theory, are described: diagonalization and the connection with modular invariance; the presentation in terms of quotients of polynomial ... More
On non-semisimple fusion rules and tensor categoriesFeb 06 2006Category theoretic aspects of non-rational conformal field theories are discussed. We consider the case that the category C of chiral sectors is a finite tensor category, i.e. a rigid monoidal category whose class of objects has certain finiteness properties. ... More
Structural Relaxations in a Simple Model Molten SaltMay 07 1996The structural relaxations of a dense, binary mixture of charged hard spheres are studied using the Mode Coupling Theory (MCT). Qualitative differences to non--ionic systems are shown to result from the long--range Coulomb interaction and charge ordering ... More
Elastic properties of colloidal solids with disorderSep 03 2012Jan 04 2013Recent progress in approaches to determine the elastic constants of solids starting from the microscopic particle interactions is reviewed. On the theoretical side, density functional theory approaches are discussed and compared to more classical ones ... More
Density waves in the shearing sheet III. Disc heatingApr 25 2001The problem of dynamical heating of galactic discs by spiral density waves is discussed using the shearing sheet model. The secular evolution of the disc is described quantitatively by a diffusion equation for the distribution function of stars in the ... More
Dim Matter in the Disks of Low Surface Brightness GalaxiesApr 23 2002An attempt is made to set constraints on the otherwise ambiguous decomposition of the rotation curves of low surface brightness galaxies into contributions due to the various components of the galaxies. For this purpose galaxies are selected which show ... More
Implications of modes of star formation for the overall dynamics of galactic disksMar 22 2001One of the present concepts for the onset of massive star formation is the Kennicutt criterion. This relates the onset of massive star formation to a general gravitational instability of the gas disks of spiral galaxies. It is often overlooked, however ... More
Bundle Gerbes and Surface HolonomyJan 14 2009Hermitian bundle gerbes with connection are geometric objects for which a notion of surface holonomy can be defined for closed oriented surfaces. We systematically introduce bundle gerbes by closing the pre-stack of trivial bundle gerbes under descent. ... More
Slow Diffeomorphisms of a Manifold with Two Dimensions Torus ActionFeb 16 2006The uniform norm of the differential of the n-th iteration of a diffeomorphism is called the growth sequence of the diffeomorphism. In this paper we show that there is no lower universal growth bound for volume preserving diffeomorphisms on manifolds ... More
Cyclic Cohomology and Higher Rank LatticesDec 01 2006Jun 18 2007We give a new proof of the absence of non-trivial idempotents in the group ring of torsion-free cocompact lattices in SL(n,C). It is based on the following procedure. We lift the class of the trace in the cyclic cohomology of the group ring to the crossed ... More
Development of a Machine Learning Based Analysis Chain for the Measurement of Atmospheric Muon Spectra with IceCubeJan 15 2017High-energy muons from air shower events detected in IceCube are selected using state of the art machine learning algorithms. Attributes to distinguish a HE-muon event from the background of low-energy muon bundles are selected using the mRMR algorithm ... More
$\mathcal{CP}$-violating effects on MSSM Higgs searchesJan 16 2018We study the effects of $\mathcal{CP}$-violating phases on the phenomenology of the Higgs sector of the MSSM. Complex parameters in the MSSM lead to $\mathcal{CP}$-violating mixing between the tree-level $\mathcal{CP}$-even and $\mathcal{CP}$-odd neutral ... More
Exploiting Weak Head Movements for Camera-based Respiration DetectionJun 19 2019In recent years, considerable progress has been made in the non-contact based detection of the respiration rate from video sequences. Common techniques either directly assess the movement of the chest due to breathing or are based on analyzing subtle ... More
Ripples and Charge Puddles in Graphene on a Metallic SubstrateApr 03 2013Jul 01 2014Graphene on a dielectric substrate exhibits spatial doping inhomogeneities, forming electron-hole puddles. Understanding and controlling the latter is of crucial importance for unraveling many of graphene's fundamental properties at the Dirac point. Here ... More