Results for "Georg Moragas-Klostermeyer"

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Modelling DESTINY+ interplanetary and interstellar dust measurements en route to the active asteroid (3200) PhaethonApr 16 2019The JAXA/ISAS spacecraft DESTINY$^+$ will be launched to the active asteroid (3200) Phaethon in 2022. Among the proposed core payload is the DESTINY+ Dust Analyzer (DDA) which is an upgrade of the Cosmic Dust Analyzer flown on the Cassini spacecraft to ... More
Mixed polarity reversible Peres gatesMar 25 2015Reversible Peres gates with more than two all over binary-valued control signals are discussed. Methods are disclosed for the low cost realization of this kind of Peres gates without requiring ancillary lines. Proper distribution of the controlled gates ... More
The Eternal Game Chromatic Number of a GraphNov 06 2018Apr 16 2019Game coloring is a well-studied two-player game in which each player properly colors one vertex of a graph at a time until all the vertices are colored. An `eternal' version of game coloring is introduced in this paper in which the vertices are colored ... More
On a notion of toric special linear systemsDec 31 2015Mar 12 2018In this note we study linear systems on complete toric varieties $X$ with an invariant point, whose orbit under the action of the automorphism group of $X$ contains the dense torus $T$ of $X$. We give a characterization of such varieties in terms of its ... More
Linear systems on the blow-up of (P^1)^nJan 26 2014Jun 19 2016In this note we study linear systems on the blow-up of $(\mathbb{P}^1)^n$ at $r$ points in very general position. We prove that the fibers of the projections $(\mathbb{P}^1)^n \rightarrow (\mathbb{P}^1)^s, 1\leq s \leq n-1$ can give contribution to the ... More
Introduction to RIMEP2: A Multi-Expression Programming System for the Design of Reversible Digital CircuitsMay 09 2014Nov 24 2014Quantum computers are considered as a future alternative to circumvent the heat dissipation problem of VLSI circuits. The synthesis of reversible circuits is a very promising area of study considering the expected further technological advances towards ... More
Jovian Dust Streams: A monitor of Io's volcanic plume activitySep 01 2003Streams of high speed dust particles originate from Jupiter's innermost Galilean moon Io. After release from Io, the particles collect electric charges in the Io plasma torus, gain energy from the co-rotating electric field of Jupiter's magnetosphere, ... More
Homoclinic bifurcation in Morse-Novikov theory, a doubling phenomenonApr 06 2016Jul 08 2016We consider a compact manifold of dimension greater than 2 and a differential form of degree one which is closed but non-exact. This form, viewed as a multi-valued function has a gradient vector field with respect to some auxiliary Riemannian metric. ... More
Invariant vector fields and the prolongation method for supersymmetric quantum systemsApr 05 2005The kinematical and dynamical symmetries of equations describing the time evolution of quantum systems like the supersymmetric harmonic oscillator in one space dimension and the interaction of a non-relativistic spin one-half particle in a constant magnetic ... More
A geometric Morse-Novikov complex with infinite series coefficientsNov 28 2018Let M be a closed n-dimensional manifold, n > 2, whose first real cohomology group H 1 (M ; R) is non-zero. We present a general method for constructing a Morse 1-form $\alpha$ on M , closed but non-exact, and a pseudo-gradient X such that the differential ... More
Two oscillators quantum groups and associated deformed coherent statesMar 21 2005Starting from a faithful five-dimensional matrix representation of the group of two independent oscillators and applying the R-matrix method we generate some classes of deformed fermionic-bosonic quantum Hopf algebras. The corresponding Lie deformed superalgebras ... More
Fundamental group of log terminal T-varietiesDec 06 2017May 31 2018In this article, we introduce an approach to study the fundamental group of a log terminal T-variety. As applications, we prove the simply connectedness of the spectrum of the Cox ring of a complex Fano variety, we compute the fundamental group of a rational ... More
sh(2/2) Superalgebra eigenstates and generalized supercoherent and supersqueezed statesApr 06 2005The superalgebra eigenstates (SAES) concept is introduced and then applied to find the SAES associated to the $sh(2/2)$ superalgebra, also known as Heisenberg--Weyl Lie superalgebra. This implies to solve a Grassmannian eigenvalue superequation. Thus, ... More
Generalized coherent and squeezed states based on the $h(1) \otimes su(2)$ algebraMar 26 2005States which minimize the Schr\"odinger--Robertson uncertainty relation are constructed as eigenstates of an operator which is a element of the $h(1) \oplus \su(2)$ algebra. The relations with supercoherent and supersqueezed states of the supersymmetric ... More
Study of the Magnetic Film Materials by Horizontal Scanning Mode for the Magnetic Force Microscopy in Magnetostatic and ac RegimesNov 02 2006The magnetic force microscopy inverse problem for the case of horizontal scanning of a tip on a linear magnetic film is introduced. We show the possibility to recover the magnetic permeability of the material from the experimental data by using the Hankel ... More
Bounded deformations of $(ε,δ)$-log canonical singularitiesMar 17 2019In this paper we study $(\epsilon,\delta)$-lc singularites, i.e. $\epsilon$-lc singularities admitting a $\delta$-plt blow-up. We prove that $n$-dimensional $(\epsilon,\delta)$-lc singularities are bounded up to a deformation, and $2$-dimensional $(\epsilon,\delta)$-lc ... More
Charged right-handed Higgsino field contribution to the chargino mass spectrum and inverse parameter problem in Left-Right Supersymmetric ModelsDec 20 2006The contribution of the charged right-handed higgsino fields to the chargino mass spectrum in the context of the Left-Right Supersymmetric Model is studied. Analytical expressions for the chargino masses assuming arbitrary CP-violating phases are given. ... More
Determining neutralino parameters in Left-Right Supersymmetric ModelsOct 04 2005We report exact analytical expressions relating the fundamental parameters describing the neutralino sector in the context of the left-right supersymmetric model. The method used for such a effects is the projector formalism deduced without take into ... More
Path-Integral Aspects of Supersymmetric Quantum MechanicsSep 02 1996In this talk we briefly review the concept of supersymmetric quantum mechanics using a model introduced by Witten. A quasi-classical path-integral evaluation for this model is performed, leading to a so-called supersymmetric quasi-classical quantization ... More
Recent Developments in Supersymmetric Quantum MechanicsMar 29 1994Apr 05 1994Some recent results in supersymmetric quantum mechanics are presented. New semi-classical approximation formulas for Witten's realization of supersymmetric quantum mechanics are discussed. Implications of the supersymmetric structure of Pauli's Hamiltonian ... More
Acceleration of GRB outflows by Poynting flux dissipationDec 21 2001Jun 24 2002We study magnetically powered relativistic outflows in which a part of the magnetic energy is dissipated internally by reconnection. For GRB parameters, and assuming that the reconnection speed scales with the Alfven speed, significant dissipation can ... More
Pseudorapidity distributions of produced charged hadrons in pp collisions at RHIC and LHC energiesJun 18 2011The energy dependence of charged-hadron production in proton-proton collisions at RHIC and LHC energies is investigated in a nonequilibrium-statistical relativistic diffusion model (RDM) with three sources for particle production. Calculated charged-hadron ... More
Rooted Trees with Probabilities RevisitedFeb 04 2013Rooted trees with probabilities are convenient to represent a class of random processes with memory. They allow to describe and analyze variable length codes for data compression and distribution matching. In this work, the Leaf-Average Node-Sum Interchange ... More
The faint young Sun problemApr 19 2012For more than four decades, scientists have been trying to find an answer to one of the most fundamental questions in paleoclimatology, the `faint young Sun problem'. For the early Earth, models of stellar evolution predict a solar energy input to the ... More
On the Expressive Power of Kleene Algebra with DomainJul 26 2015Aug 02 2015It is shown that antidomain semirings are more expressive than test semirings and that Kleene algebras with domain are more expressive than Kleene algebras with tests. It is also shown that Kleene algebras with domain are expressive for propositional ... More
On the expected runtime of multiple testing algorithms with bounded errorJul 27 2018Jan 28 2019Consider the testing of multiple hypotheses in the setting where the p-values of all hypotheses are unknown and thus have to be approximated using Monte Carlo simulations. One class of algorithms published in the literature for this scenario ensures guarantees ... More
On the Application of ISO 26262 in Control Design for Automated VehiclesApr 12 2018Research on automated vehicles has experienced an explosive growth over the past decade. A main obstacle to their practical realization, however, is a convincing safety concept. This question becomes ever more important as more sophisticated algorithms ... More
Alternative interpretation of the Plücker quadric's ambient space and its applicationMar 26 2018It is well-known that there exists a bijection between the set of lines of the projective 3-dimensional space $P^3$ and all real points of the so-called Pl\"ucker quadric $\Psi$. Moreover one can identify each point of the Pl\"ucker quadric's ambient ... More
The Emptiness Problem for Valence Automata over Graph MonoidsOct 20 2017This work studies which storage mechanisms in automata permit decidability of the emptiness problem. The question is formalized using valence automata, an abstract model of automata in which the storage mechanism is given by a monoid. For each of a variety ... More
Beyond the thermal model in relativistic heavy-ion collisionsMay 31 2016Jun 27 2016Deviations from thermal distribution functions of produced particles in relativistic heavy-ion collisions are discussed as indicators for nonequilibrium processes. The focus is on rapidity distributions of produced charged hadrons as functions of collision ... More
Interpolation categories for homology theoriesDec 19 2004Feb 25 2006For a homological functor from a triangulated category to an abelian category satisfying some technical assumptions we construct a tower of interpolation categories. These are categories over which the functor factorizes and which capture more and more ... More
Raynaud's vector bundles and base points of the generalized Theta divisorJul 14 2006We study base points of the generalized Theta-divisor on the moduli space of vector bundles on a smooth algebraic curve X of genus g defined over an algebraically closed field. To do so, we use the derived categories D(Pic(X)), D(Jac(X)), and the equivalence ... More
Positivity of relative canonical bundles and applicationsJan 13 2012Given a family $f:\mathcal X \to S$ of canonically polarized manifolds, the unique K\"ahler-Einstein metrics on the fibers induce a hermitian metric on the relative canonical bundle $\mathcal K_{\mathcal X/S}$. We use a global elliptic equation to show ... More
Restriction of stable rank two vector bundles in arbitrary characteristicApr 20 1999Let $X$ be a smooth variety defined over an algebraically closed field of arbitrary characteristic and $\O_X(H)$ be a very ample line bundle on $X$. We show that for a semistable $X$-bundle $E$ of rank two, there exists an integer $m$ depending only on ... More
Motion of inertial particles in Gaussian fields driven by an infinite-dimensional fractional Brownian motionMar 18 2012We study the motion of an inertial particle in a fractional Gaussian random field. The motion of the particle is described by Newton's second law, where the force is proportional to the difference between a background fluid velocity and the particle velocity. ... More
Divided Differences of Multivariate Implicit FunctionsFeb 29 2012Under general conditions, the equation $g(x^1, ..., x^q, y) = 0$ implicitly defines $y$ locally as a function of $x^1, ..., x^q$. In this article, we express divided differences of $y$ in terms of divided differences of $g$, generalizing a recent formula ... More
Implicit Divided Differences, Little Schröder Numbers, and Catalan NumbersApr 12 2012Jan 31 2015Under general conditions, the equation $g(x,y) = 0$ implicitly defines $y$ locally as a function of $x$. In this short note we study the combinatorial structure underlying a recently discovered formula for the divided differences of $y$ expressed in terms ... More
Weyl Groups with Coxeter Presentation and Presentation by ConjugationJul 22 2006We investigate which Weyl groups have a Coxeter presentation and which of them at least have the presentation by conjugation with respect to their root system. For most concepts of root systems the Weyl group has both. In the context of extended affine ... More
On reduced stable pair invariantsMay 16 2016Let $X = S \times E$ be the product of a K3 surface $S$ and an elliptic curve $E$. Reduced stable pair invariants of $X$ can be defined via (1) cutting down the reduced virtual class with incidence conditions or (2) the Behrend function weighted Euler ... More
A Serre derivative for even weight Jacobi FormsSep 25 2012Jun 11 2014Using deformed or twisted Eisenstein Series, we construct a Jacobi-Serre derivative on even-weight Jacobi forms that generalizes the classical Serre derivative on modular forms. As an application, we obtain Ramanujan equations for the index $1$ Eisenstein ... More
Produced charged hadrons in central Pb + Pb collisions at LHC energies in the RDMFeb 16 2011Apr 13 2011The energy dependence of charged-hadron production in relativistic heavy-ion collisions is investigated in a nonequilibrium-statistical relativistic diffusion model (RDM) with three sources. Theoretical pseudorapidity distributions are compared with Au ... More
Proof Theory at Work: Complexity Analysis of Term Rewrite SystemsJul 31 2009Dec 30 2009This thesis is concerned with investigations into the "complexity of term rewriting systems". Moreover the majority of the presented work deals with the "automation" of such a complexity analysis. The aim of this introduction is to present the main ideas ... More
Duality Construction of Moduli SpacesAug 29 1997We show for the moduli space of rank-2 coherent sheaves on an algebraic surface that there exists a 'dual' moduli space. This dual space allows a construction of the first one without using the GIT construction. Furthermore, we obtain a Barth-morphism, ... More
On Newton-Okounkov bodies of Graded Linear SeriesJan 14 2018We generalize the theory of Newton-Okounkov bodies of big divisors to the case of graded linear series. One of the results is the generalization of slice formulas and the existence of generic Newton-Okounkov bodies for birational graded linear series. ... More
Generalized Albanese morphismsApr 04 2003Sep 27 2004We define generalizations of the Albanese variety for a projective variety X. The generalized Albanese morphisms X --> Alb_r(X) contract those curves C in X for which the induced morphism Hom(\pi_1(X),U(r)) --> Hom(\pi_1(C),U(r)) has a finite image. Thus, ... More
Symbols and exact regularity of symmetric pseudo-splines of any arityNov 02 2016Pseudo-splines form a family of subdivision schemes that provide a natural blend between interpolating schemes and approximating schemes, including the Dubuc-Deslauriers schemes and B-spline schemes. Using a generating function approach, we derive expressions ... More
Accelerated Portfolio Optimization with Conditional Value-at-Risk Constraints using a Cutting-Plane MethodAug 12 2014Financial portfolios are often optimized for maximum profit while subject to a constraint formulated in terms of the Conditional Value-at-Risk (CVaR). This amounts to solving a linear problem. However, in its original formulation this linear problem has ... More
Fixed Point Theorem for Non-Self Maps of Regions in the PlaneDec 15 2011May 03 2013Let X and Y be compact, simply connected and locally connected subsets of R^2, and let f : X -> Y be a homeomorphism isotopic to the identity on X. Generalizing Brouwer's plane translation theorem for self-maps of the plane, we prove that f has no recurrent ... More
Explicit thermostatics of certain classical one-dimensional lattice models by harmonic analysisMar 28 1994A certain class of one-dimensional classical lattice models is considered. Using the method of abstract harmonic analysis explicit thermostatic properties of such models are derived. In particular, we discuss the low-temperature behavior of some of these ... More
Exchange currents in radiative hyperon decays and hyperon charge radiiOct 06 1998Radiative decays of decuplet hyperons and octet hyperon charge radii are evaluated in a chiral constituent quark model emphasizing the role of exchange currents. Exchange currents largely cancel for the M1 decay amplitudes, while they dominate the E2 ... More
An extension theorem for hermitian line bundlesJul 22 2015May 11 2016We prove a general extension theorem for holomorphic line bundles on reduced complex spaces, equipped with singular hermitian metrics, whose curvature currents can be extended as positive, closed currents. The result has applications to various moduli ... More
Complex-Valued Random Vectors and Channels: Entropy, Divergence, and CapacityMay 04 2011Recent research has demonstrated significant achievable performance gains by exploiting circularity/non-circularity or propeness/improperness of complex-valued signals. In this paper, we investigate the influence of these properties on important information ... More
Silent Transitions in Automata with StorageFeb 15 2013We consider the computational power of silent transitions in one-way automata with storage. Specifically, we ask which storage mechanisms admit a transformation of a given automaton into one that accepts the same language and reads at least one input ... More
On the capabilities of grammars, automata, and transducers controlled by monoidsMar 17 2011During the last decades, classical models in language theory have been extended by control mechanisms defined by monoids. We study which monoids cause the extensions of context-free grammars, finite automata, or finite state transducers to exceed the ... More
Equilibration in finite Bose systemsDec 07 2017Feb 08 2018The equilibration of a finite Bose system is modelled using a gradient expansion of the collision integral that leads to a nonlinear transport equation. For constant transport coefficients, it is solved in closed form through a nonlinear transformation. ... More
Moduli of canonically polarized manifolds, higher order Kodaira-Spencer maps, and an analogy to Calabi-Yau manifoldsFeb 24 2017Jan 23 2018A Finsler metric, whose holomorphic curvature is bounded from above by a negative constant, is constructed on the moduli stack of canonically polarized manifolds including singularities. Demailly's version of Ahlfors' lemma yields hyperbolicity of the ... More
A note on random samples of Lie algebrasJul 09 2014Recently, Paiva and Teixeira (arXiv:1108.4396) showed that the structure constants of a Lie algebra are the solution of a system of linear equations provided a certain subset of the structure constants are given a-priori. Here it is noted that Lie algebras ... More
Gromov-Witten invariants of the Hilbert schemes of points of a K3 surfaceJun 04 2014Nov 03 2015We study the enumerative geometry of rational curves on the Hilbert schemes of points of a K3 surface. Let $S$ be a K3 surface and let $\mathsf{Hilb}^d(S)$ be the Hilbert scheme of $d$ points of $S$. In case of elliptically fibered K3 surfaces $S \to ... More
Dynamics of a Continuous Piecewise Affine Map of the SquareMay 18 2013We present a one-parameter family of continuous, piecewise affine, area preserving maps of the square, which are inspired by a dynamical system in game theory. Interested in the coexistence of stochastic and (quasi-)periodic behaviour, we investigate ... More
Compactifications of the Drinfeld half space over a Finite FieldApr 18 2018When considered as a Deligne-Lusztig variety, the Drinfeld half space $\Omega_V$ over a finite field $k$ has a compactification whose boundary divisor is normal crossing and which can be obtained by successively blowing-up projective space along linear ... More
Injective completion with respect to homologyDec 19 2004Generalizing F-nilpotent completion for a ring spectrum F we first define the notion of completion with respect to a thick subcategory in a monogenic stable homotopy category. Specializing this to the thick subcategory generated by F-injectives gives ... More
A Brascamp-Lieb type covariance estimateFeb 20 2014In this article, we derive a new covariance estimate. The estimate has a similar structure as the Brascamp-Lieb inequality and is optimal for ferromagnetic Gaussian measures. It can be naturally applied to deduce decay of correlations of lattice systems ... More
Quantum and classical stochastic dynamics: Exactly solvable models by supersymmetric methodsOct 23 1998A supersymmetric method for the construction of so-called conditionally exactly solvable quantum systems is reviewed and extended to classical stochastic dynamical systems characterized by a Fokker-Planck equation with drift. A class of drift-potentials ... More
Exchange Currents in Radiative Hyperon DecaysJun 15 1998A short overview of motivations and successes of two-body exchange currents between constituent quarks for electromagnetic hadron observables like charge radii, magnetic and quadrupole moments is given. We then predict and analyze exchange current effects ... More
Climate Modelling of Mass-Extinction Events: A ReviewJun 18 2009Despite tremendous interest in the topic and decades of research, the origins of the major losses of biodiversity in the history of life on Earth remain elusive. A variety of possible causes for these mass-extinction events have been investigated, including ... More
On the Throughput/Bit-Cost Tradeoff in CSMA Based Cooperative NetworksJun 05 2009Nov 04 2009Wireless local area networks (WLAN) still suffer from a severe performance discrepancy between different users in the uplink. This is because of the spatially varying channel conditions provided by the wireless medium. Cooperative medium access control ... More
Particle production sources at LHC energiesJan 09 2013Feb 18 2013Particle production sources at RHIC and LHC energies are investigated in pseudorapidity space. A nonequilibrium-statistical relativistic diffusion model (RDM) with three sources is applied to the analysis of charged-hadron distributions in AuAu collisions ... More
Optimal Non-Uniform Mapping for Probabilistic ShapingAug 06 2012Jul 07 2014The construction of optimal non-uniform mappings for discrete input memoryless channels (DIMCs) is investigated. An efficient algorithm to find optimal mappings is proposed and the rate by which a target distribution is approached is investigated. The ... More
On the Relation between Solar Activity and Clear-Sky Terrestrial IrradianceSep 04 2012Oct 09 2012The Mauna Loa Observatory record of direct-beam solar irradiance measurements for the years 1958-2010 is analysed to investigate the variation of clear-sky terrestrial insolation with solar activity over more than four solar cycles. The raw irradiance ... More
Limits on a CP-violating scalar axion-nucleon interactionMay 08 2012Jul 29 2012Axions or similar hypothetical pseudoscalar bosons may have a small CP-violating scalar Yukawa interaction g_s(N) with nucleons, causing macroscopic monopole-dipole forces. Torsion-balance experiments constrain g_p(e) g_s(N), whereas g_p(N) g_s(N) is ... More
Neutrinos and the starsJan 08 2012May 19 2012The role of neutrinos in stars is introduced for students with little prior astrophysical exposure. We begin with neutrinos as an energy-loss channel in ordinary stars and conversely, how stars provide information on neutrinos and possible other low-mass ... More
CP violation in $B^0_s$ mixing with LHCbDec 05 2011The determination of the CP-violating phase $\phi_s$ in $B^0_s \rightarrow J/\psi \phi$ decays is one of the key goals of the LHCb experiment. Its value is predicted to be very small in the Standard Model but can be significantly enhanced in many models ... More
Supersymmetry on the lattice and the status of the Super-Yang-Mills simulationsNov 03 2010Supersymmetry (SUSY) and supersymmetric field theories are an interesting topic for numerical lattice simulations. Similar to the chiral symmetry there is also no local realization of (interacting) supersymmetry on the lattice. I briefly review the basic ... More
Gromov-Witten theory of K3 x P1 and quasi-Jacobi formsMay 17 2016Let $S$ be a K3 surface with primitive curve class $\beta$. We completely solve the relative Gromov-Witten theory of $S \times \mathbb{P}^1$ in classes $(\beta,1)$ and $(\beta,2)$. The generating series are quasi-Jacobi forms and equal to a corresponding ... More
The complexity of downward closure comparisonsMay 10 2016The downward closure of a language is the set of all (not necessarily contiguous) subwords of its members. It is well-known that the downward closure of every language is regular. Moreover, recent results show that downward closures are computable for ... More
Gromov-Witten theory of $\mathrm{K3} \times \mathbb{P}^1$ and quasi-Jacobi formsMay 17 2016Oct 12 2017Let $S$ be a K3 surface with primitive curve class $\beta$. We solve the relative Gromov-Witten theory of $S \times \mathbb{P}^1$ in classes $(\beta,1)$ and $(\beta,2)$. The generating series are quasi-Jacobi forms and equal to a corresponding series ... More
On reduced stable pair invariantsMay 16 2016Sep 23 2017Let $X = S \times E$ be the product of a K3 surface $S$ and an elliptic curve $E$. Reduced stable pair invariants of $X$ can be defined via (1) cutting down the reduced virtual class with incidence conditions or (2) the Behrend function weighted Euler ... More
Ultraviolet energy dependence of particle production sources in relativistic heavy-ion collisionsJan 13 2015The energy dependence of particle production sources in relativistic heavy-ion collisions is investigated from RHIC to LHC energies. Whereas charged-hadron production in the fragmentation sources follows a ln(s_NN/s_0) law, particle production in the ... More
An extension theorem for hermitian line bundlesJul 22 2015Mar 30 2017We prove a general extension theorem for holomorphic line bundles on reduced complex spaces, equipped with singular hermitian metrics, whose curvature currents can be extended as positive, closed currents. The result has applications to various moduli ... More
An approach to computing downward closuresMar 03 2015Jun 01 2015The downward closure of a word language is the set of all (not necessarily contiguous) subwords of its members. It is well-known that the downward closure of any language is regular. While the downward closure appears to be a powerful abstraction, algorithms ... More
Kinematic interpretation of the Study quadric's ambient spaceJul 31 2017It is well known that real points of the Study quadric (sliced along a 3-dimensional generator space) correspond to displacements of the Euclidean 3-space. But we still lack of a kinematic meaning for the points of the ambient 7-dimensional projective ... More
EXPODE -- Advanced Exponential Time Integration Toolbox for MATLABApr 17 2014We present a MATLAB toolbox for five different classes of exponential integrators for solving (mildly) stiff ordinary differential equations or time-dependent partial differential equations. For the efficiency of such exponential integrators it is essential ... More
Probabilistic Signal Shaping for Bit-Metric DecodingJan 23 2014Apr 20 2014A scheme is proposed that combines probabilistic signal shaping with bit-metric decoding. The transmitter generates symbols according to a distribution on the channel input alphabet. The symbols are labeled by bit strings. At the receiver, the channel ... More
Curvature of higher direct images and applications (Curvature of $R^{n-p}f_*Ω^p_{X/S}(K_{X/S}^{\otimes m})$ and applications)Feb 25 2010May 19 2010Given an effectively parameterized family $f:X\to S$ of canonically polarized manifolds, the K\"ahler-Einstein metrics on the fibers induce a hermitian metric on the relative canonical bundle $K_{X/S}$. We use a global elliptic equation to show that this ... More
The Relative Chern Character and RegulatorsJul 08 2010In this thesis we construct a modified version of Karoubi's relative Chern character for smooth varieties over the complex numbers or the ring of integers in a p-adic number field. Comparison results with the Deligne-Beilinson Chern character and the ... More
Fitting and Analysis Technique for Inconsistent Nuclear DataMar 02 2018Consistent experiment data are crucial to adjust parameters of physics models and to determine best estimates of observables. However, often experiment data are not consistent due to unrecognized systematic errors. Standard methods of statistics such ... More
Raynaud vector bundlesJun 27 2007We construct vector bundles $R^r_\mu$ on a smooth projective curve $X$ having the property that for all sheaves $E$ of slope $\mu$ and rank $r$ on $X$ we have an equivalence: $E$ is a semistable vector bundle $\iff$ $Hom(R^r_\mu,E)=0$. As a byproduct ... More
SU(r,L) is separably unirationalOct 22 2008We show that the moduli space of SU_X(r,L) of rank r bundles of fixed determinant L on a smooth projective curve X is separably unirational.
Minimal bundles and fine moduli spacesMar 13 2009We study sheaves E on a smooth projective curve X which are minimal with respect to the property that $h^0(E \otimes L) >0$ for all line bundles L of degree zero. We show that these sheaves define ample divisors D(E) on the Picard torus Pic(X). Next we ... More
On the homotopy theory of n-typesApr 24 2006An n-truncated model structure on simplicial (pre-)sheaves is described having as weak equivalences maps that induce isomorphisms on certain homotopy sheaves only up to degree n. Starting from one of Jardine's intermediate model structures we construct ... More
EXPODE - Advanced Exponential Time Integration Toolbox for MATLAB, Code DocumentationAug 12 2011Dec 08 2011EXPODE is a MATLAB toolbox for exponential time integration. It supports exponential Runge-Kutta- and Rosenbrock-methods, linearized and non-linearized multistep-methods and the EXP4. We support evaluation of the arising matrix functions either directly ... More
Risk aggregation with empirical margins: Latin hypercubes, empirical copulas, and convergence of sum distributionsAug 11 2015This paper studies convergence properties of multivariate distributions constructed by endowing empirical margins with a copula. This setting includes Latin Hypercube Sampling with dependence, also known as the Iman--Conover method. The primary question ... More
Residual intersection theory with reducible schemesNov 07 2001We develop a formula (Theorem 5.1) which allows to compute top Chern classes of vector bundles on the vanishing locus $V(s)$ of a section of this bundle. This formula particularly applies in the case when $V(s)$ is the union of locally complete intersections ... More
The approach of Otto-Reznikoff revisitedSep 03 2013Apr 10 2014In this article we consider a lattice system of unbounded continuos spins. Otto & Reznikoff used the two-scale approach to show that exponential decay of correlations yields a logarithmic Sobolev inequality (LSI) with uniform constant in the system size. ... More
Arithmetics with multiple testing proceduresJul 14 2016Statistical discoveries are often obtained through multiple hypothesis testing. A variety of procedures exists to evaluate multiple hypotheses, for instance the ones of Benjamini-Hochberg, Bonferroni, Holm or Sidak. We are particularly interested in multiple ... More
Importance sampling for the simulation of reinsurance lossesMar 30 2013Importance sampling is a well developed method in statistics. Given a random variable $X$, the problem of estimating its expected value $\mu$ is addressed. The standard approach is to use the sample mean as an estimator $\bar x$. In importance sampling, ... More
Deciding Monotone Duality and Identifying Frequent Itemsets in Quadratic LogspaceDec 09 2012Aug 22 2013The monotone duality problem is defined as follows: Given two monotone formulas f and g in iredundant DNF, decide whether f and g are dual. This problem is the same as duality testing for hypergraphs, that is, checking whether a hypergraph H consists ... More
AXIONS IN ASTROPHYSICS AND COSMOLOGYFeb 21 1995Mar 23 1995If axions exist they are efficiently produced in the hot and dense interior of stars, providing a novel energy-loss mechanism. In order to avoid a conflict with the observed properties of stars, one can derive a lower limit on the Peccei-Quinn scale (an ... More
Abstract tropical linear programmingDec 06 2016Analogously to classical oriented matroid programming, we give the first feasibility algorithm for signed tropical oriented matroids, which encode the structure of tropical linear inequality systems. The feasibility problem for tropical linear inequality ... More
Achievable Rates for Shaped Bit-Metric DecodingOct 29 2014May 28 2016A new achievable rate for bit-metric decoding (BMD) is derived using random coding arguments. The rate expression can be evaluated for any input distribution, and in particular the bit-levels of binary input labels can be stochastically dependent. Probabilistic ... More