Results for "Tobias Neumann"

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Off-shell single-top-quark production in the Standard Model Effective Field TheoryMar 26 2019We present a fully differential and spin-dependent $t$-channel single-top-quark calculation at next-to-leading order (NLO) in QCD including off-shell effects by using the complex mass scheme in the Standard Model (SM) and in the Standard Model Effective ... More
$Zγ$ production at NNLO including anomalous couplingsAug 09 2017In this paper we present a next-to-next-to-leading order (NNLO) QCD calculation of the processes $pp\rightarrow l^+l^-\gamma$ and $pp\rightarrow \nu\bar\nu\gamma$ that we have implemented in MCFM. Our calculation includes QCD corrections at NNLO both ... More
Recent Developments in Gluon Fusion Higgs CalculationsOct 03 2018During recent years perturbative fixed order and resummation calculations have decreased uncertainties on predictions for gluon fusion Higgs production cross sections tremendously. Most exciting results have been published just this year. In these proceedings ... More
Top-mass effects in differential Higgs production through gluon fusion at order α_s^4Jun 01 2012Effects from a finite top quark mass on differential distributions in the Higgs+jet production cross section through gluon fusion are studied at next-to-leading order in the strong coupling, i.e. $O(\alpha_s^4)$. Terms formally subleading in $1/m_t$ are ... More
NLO Higgs+jet at large transverse momenta including top quark mass effectsFeb 08 2018We present a next-to-leading order calculation of H+jet in gluon fusion including the effect of a finite top quark mass $m_t$ at large transverse momenta. Using the recently published two-loop amplitudes in the high energy expansion and our previous setup ... More
Greedy Maximization of Functions with Bounded Curvature under Partition Matroid ConstraintsNov 13 2018Feb 21 2019We investigate the performance of a deterministic GREEDY algorithm for the problem of maximizing functions under a partition matroid constraint. We consider non-monotone submodular functions and monotone subadditive functions. Even though constrained ... More
The Higgs boson at high $p_T$Sep 01 2016We present a calculation of $H+j$ at NLO including the effect of a finite top-mass. Where possible we include the complete dependence on $m_t$. This includes the leading order amplitude, the infrared poles of the two-loop amplitude and the real radiation ... More
Finite top-mass effects in gluon-induced Higgs production with a jet-veto at NNLOAug 28 2014Effects from a finite top quark mass on the H+n-jet cross section through gluon fusion are studied for $n=0/n\ge 1$ at NNLO/NLO QCD. For this purpose, sub-leading terms in $1/m_t$ are calculated. We show that the asymptotic expansion of the jet-vetoed ... More
Results and techniques for higher order calculations within the gradient flow formalismMay 02 2019We describe in detail the implementation of a systematic perturbative approach to observables in the QCD gradient-flow formalism. This includes a collection of all relevant Feynman rules of the five-dimensional field theory and the composite operators ... More
Quasi-random Agents for Image Transition and AnimationOct 20 2017Quasi-random walks show similar features as standard random walks, but with much less randomness. We utilize this established model from discrete mathematics and show how agents carrying out quasi-random walks can be used for image transition and animation. ... More
The perturbative QCD gradient flow to three loopsJun 12 2016Jun 29 2016The gradient flow in QCD is treated perturbatively through next-to-next-to-leading order in the strong coupling constant. The evaluation of the relevant momentum and flow-time integrals is described, including various means of validation. For the vacuum ... More
Pareto Optimization for Subset Selection with Dynamic Cost ConstraintsNov 14 2018In this paper, we consider the subset selection problem for function $f$ with constraint bound $B$ which changes over time. We point out that adaptive variants of greedy approaches commonly used in the area of submodular optimization are not able to maintain ... More
Valence of complex-valued planar harmonic functionsJan 26 2004The valence of a function $f$ at a point $w$ is the number of distinct, finite solutions to $f(z) = w$. Let $f$ be a complex-valued harmonic function in an open set $R \subseteq \mathbb{C}$. Let $S$ denote the critical set of $f$ and $C(f)$ the global ... More
Multiplicative Approximations, Optimal Hypervolume Distributions, and the Choice of the Reference PointSep 16 2013Many optimization problems arising in applications have to consider several objective functions at the same time. Evolutionary algorithms seem to be a very natural choice for dealing with multi-objective problems as the population of such an algorithm ... More
High-Speed Query Processing over High-Speed NetworksFeb 25 2015Nov 02 2015Modern database clusters entail two levels of networks: connecting CPUs and NUMA regions inside a single server in the small and multiple servers in the large. The huge performance gap between these two types of networks used to slow down distributed ... More
Predicting the Energy Output of Wind Farms Based on Weather Data: Important Variables and their CorrelationSep 09 2011Wind energy plays an increasing role in the supply of energy world-wide. The energy output of a wind farm is highly dependent on the weather condition present at the wind farm. If the output can be predicted more accurately, energy suppliers can coordinate ... More
Changing minds about electric cars: An empirically grounded agent-based modeling approachMay 23 2014Aug 26 2014The diffusion of electric vehicles (EVs) is considered an effective policy strategy to meet greenhouse gas reduction targets. For large-scale adoption, however, demand-side oriented policy measures are required, based on consumers transport needs, values ... More
Influence of the Hall-bar geometry on harmonic Hall voltage measurements of spin-orbit torquesApr 20 2018Harmonic Hall voltage measurements are a wide-spread quantitative technique for the measurement of spin-orbit induced effective fields in heavy-metal / ferromagnet heterostructures. In the vicinity of the voltage pickup lines in the Hall bar, the current ... More
Kuperberg invariants for balanced sutured 3-manifoldsApr 11 2019We construct quantum invariants of balanced sutured 3-manifolds with a $Spin^{c}$ structure out of an involutive (possibly non-unimodular) Hopf superalgebra $H$. If $H$ is the Borel subalgebra of $U_{q}(\mathfrak{gl}(1|1))$, we show that our invariant ... More
A short proof that positive generation implies the Hanna Neumann ConjectureFeb 13 2007We give a very short proof that a subgroup of a free group that is positively generated cannot be part of a counterexample to the Generalized Hanna Neumann Conjecture.
Quantitative perturbative study of convergence to equilibrium for collisional kinetic models in the torusJul 21 2006For a general class of linear collisional kinetic models in the torus, including in particular the linearized Boltzmann equation for hard spheres, the linearized Landau equation with hard and moderately soft potentials and the semi-classical linearized ... More
Stability of steady states in kinetic Fokker-Planck equations for Bosons and FermionsJul 31 2007We study a class of nonlinear kinetic Fokker-Planck type equations modeling quantum particles which obey the Bose-Einstein and Fermi-Dirac statistics, respectively. We establish the existence of classical solutions in the perturbative regime and prove ... More
Nontrivial rational polynomials in two variables have reducible fibresMay 21 1998It has been proved several times in the literature that a polynomial map from $C^2$ to $C$ with irreducible rational fibers cannot be a component of a counterexample to the Jacobian Conjecture. This note points out that this result is empty: it is implicit ... More
Rationality problems for Chern-Simons invariantsDec 04 1997This paper makes certain observations regarding some conjectures of Milnor and Ramakrishnan in hyperbolic geometry and algebraic K-theory. As a consequence of our observations, we obtain new results and conjectures regarding the rationality and irrationality ... More
The End Curve Theorem for normal complex surface singularitiesApr 29 2008We prove the "End Curve Theorem," which states that a normal surface singularity $(X,o)$ with rational homology sphere link $\Sigma$ is a splice-quotient singularity if and only if it has an end curve function for each leaf of a good resolution tree. ... More
The notion of $ψ$-weak dependence and its applications to bootstrapping time seriesJun 26 2008We give an introduction to a notion of weak dependence which is more general than mixing and allows to treat for example processes driven by discrete innovations as they appear with time series bootstrap. As a typical example, we analyze autoregressive ... More
Lipschitz geometry of complex curvesFeb 05 2013Feb 11 2013We describe the Lipschitz geometry of complex curves. For the most part this is well known material, but we give a stronger version even of known results. In particular, we give a quick proof, without any analytic restrictions, that the outer Lipschitz ... More
Nonparametric estimation for Lévy processes from low-frequency observationsSep 13 2007May 29 2008We suppose that a L\'evy process is observed at discrete time points. A rather general construction of minimum-distance estimators is shown to give consistent estimators of the L\'evy-Khinchine characteristics as the number of observations tends to infinity, ... More
A Practical Maximum Clique Algorithm for Matching with Pairwise ConstraintsFeb 05 2019A popular paradigm for 3D point cloud registration is by extracting 3D keypoint correspondences, then estimating the registration function from the correspondences using a robust algorithm. However, many existing 3D keypoint techniques tend to produce ... More
How to Evaluate Controlled Natural LanguagesJul 07 2009This paper presents a general framework how controlled natural languages can be evaluated and compared on the basis of user experiments. The subjects are asked to classify given statements (in the language to be tested) as either true or false with respect ... More
AceWiki: Collaborative Ontology Management in Controlled Natural LanguageJul 29 2008AceWiki is a prototype that shows how a semantic wiki using controlled natural language - Attempto Controlled English (ACE) in our case - can make ontology management easy for everybody. Sentences in ACE can automatically be translated into first-order ... More
Lebesgue measure theory and integration theory on non-archimedean real closed fields with archimedean value groupSep 08 2014Feb 02 2016Given a non-archimedean real closed field with archimedean value group which contains the reals, we establish for the category of semialgebraic sets and functions a full Lebesgue measure and integration theory such that the main results from the classical ... More
Auslander-Reiten sequences, Brown-Comenetz duality, and the $K(n)$-local generating hypothesisMar 30 2016In this paper, we construct a version of Auslander-Reiten sequences for the $K(n)$-local stable homotopy category. In particular, the role of the Auslander-Reiten translation is played by the local Brown-Comenetz duality functor. As an application, we ... More
Inclusive Rare B DecaysJun 05 2001Jun 13 2001We review the present status of rare B decays, focusing on inclusive decay modes and their role in our search for new physics. We also briefly discuss direct CP violation in rare B decays and the rare kaon decays $K^+\to \pi^+\nu\bar{\nu}$ and $K_L \to ... More
Rare Decays as a Probe for New PhysicsDec 19 2006We discuss the indirect search for new degrees of freedom beyond the standard model, within flavour physics. In particular, we analyse the minimal flavour violation hypothesis and its phenomenological implications, especially the large-tan beta scenario ... More
New physics search in the LHCb eraSep 25 2008Dec 23 2008We present theoretical and experimental preparations for an indirect search for new physics using the rare decay $\bar B_d \to \bar K^* l^+ l^-$. We design new observables with very small theoretical uncertainties and good experimental resolution.
Piecewise Weierstrass preparation and division for o-minimal holomorphic functionsJun 08 2016Oct 12 2016Given an o-minimal structure expanding the field of reals, we show a piecewise Weierstrass preparation theorem and a piecewise Weierstrass division theorem for definable holomorphic functions. In the semialgebraic setting and for the structure of globally ... More
Feedback between interacting transport channelsMar 12 2015A model for autonomous feedback control of particle transport through a large number of channels is introduced. Interactions among the particles can lead to a strong suppression of fluctuations in the particle number statistics. Within a mean-field type ... More
Divisors on Projective Hibi VarietiesJun 08 2015We compute the divisor class group and the Picard group of projective varieties with Hibi rings as homogeneous coordinate rings. These varieties are precisely the toric varieties associated to order polytopes. We use tools from the theory of toric varieties ... More
Oddness of residually reducible Galois representationsNov 28 2016We show that suitable congruences between polarized automorphic forms over a CM field always produce elements in the Selmer group for exactly the +/--Asai (aka tensor induction) representation that is critical in the sense of Deligne. For this we relate ... More
Global existence without decay for quadratic Klein-Gordon equationsSep 07 2012Sep 19 2012The Cauchy problem for quadratic Klein-Gordon systems is considered in two spatial dimensions and higher under a suitable non-resonance condition on the masses, including the main case of equal masses. A global well-posedness and scattering result is ... More
Velocity Polytopes of Periodic Graphs and a No-Go Theorem for Digital PhysicsSep 09 2011Jun 17 2013A periodic graph in dimension $d$ is a directed graph with a free action of $\Z^d$ with only finitely many orbits. It can conveniently be represented in terms of an associated finite graph with weights in $\Z^d$, corresponding to a $\Z^d$-bundle with ... More
Computing topological zeta functions of groups, algebras, and modules, IISep 17 2014Building on our previous work (arXiv:1405.5711), we develop the first practical algorithm for computing topological zeta functions of nilpotent groups, non-associative algebras, and modules. While we previously depended upon non-degeneracy assumptions, ... More
Resource convertibility and ordered commutative monoidsApr 14 2015Jul 02 2015Resources and their use and consumption form a central part of our life. Many branches of science and engineering are concerned with the question of which given resource objects can be converted into which target resource objects. For example, information ... More
Quantum analogues of Hardy's nonlocality paradoxJun 12 2010Apr 04 2011Hardy's nonlocality is a "nonlocality proof without inequalities": it exemplifies that quantum correlations can be qualitatively stronger than classical correlations. This paper introduces variants of Hardy's nonlocality in the CHSH scenario which are ... More
Quantum correlations in the temporal CHSH scenarioMay 19 2010Mar 26 2014We consider a temporal version of the CHSH scenario using projective measurements on a single quantum system. It is known that quantum correlations in this scenario are fundamentally more general than correlations obtainable with the assumptions of macroscopic ... More
On the existence of quantum representations for two dichotomic measurementsAug 18 2009Feb 16 2010Under which conditions do outcome probabilities of measurements possess a quantum-mechanical model? This kind of problem is solved here for the case of two dichotomic von Neumann measurements which can be applied repeatedly to a quantum system with trivial ... More
A Chomsky-Schützenberger representation for weighted multiple context-free languagesJun 13 2016We prove a Chomsky-Sch\"utzenberger representation theorem for multiple context-free languages weighted over complete commutative strong bimonoids.
An automata characterisation for multiple context-free languagesJun 09 2016Sep 23 2016We introduce tree stack automata as a new class of automata with storage and identify a restricted form of tree stack automata that recognises exactly the multiple context-free languages.
Extra dimension-inspired models: Z', W', dijet resonances, black hole searchesDec 08 2015Dec 11 2015I give a summary of BSM searches performed by the ATLAS and CMS experiments with an focus on heavy gauge bosons, extra dimensions and quantum black holes. The presented results use data collected during 2012 when the LHC operated at an center of mass ... More
Non-loose Legendrian spheres with trivial Contact Homology DGAFeb 16 2015Feb 13 2018Loose Legendrian n-submanifolds, for n at least 2, were introduced by Murphy and proved to be flexible in the h-principle sense: any two loose Legendrian submanifolds that are formally Legendrian isotopic are also actually Legendrian isotopic. Legendrian ... More
Quantum logic is undecidableJul 20 2016Nov 04 2016We investigate the first-order theory of closed subspaces of complex Hilbert spaces in the signature $(\lor,\perp,0,1)$, where `$\perp$' is the orthogonality relation. Our main result is that already its purely implicational fragment is undecidable: there ... More
Transition probabilities and measurement statistics of postselected ensemblesMar 23 2010Jul 20 2010It is well-known that a quantum measurement can enhance the transition probability between two quantum states. Such a measurement operates after preparation of the initial state and before postselecting for the final state. Here we analyze this kind of ... More
Hecke algebras and affine flag varieties in characteristic pJan 24 2015Oct 02 2015Let G be a split semi-simple p-adic group and let H be its Iwahori-Hecke algebra with coefficients in the algebraic closure k of the finite field with p elements. Let F be the affine flag variety over k associated with G. We show, in the simply connected ... More
Morse flow trees and Legendrian contact homology in 1-jet spacesSep 16 2005Let $L\subset J^1(M)$ be a Legendrian submanifold of the 1-jet space of a Riemannian $n$-manifold $M$. A correspondence is established between rigid flow trees in $M$ determined by $L$ and boundary punctured rigid pseudo-holomorphic disks in $T^\ast M$, ... More
Polyhedral duality in Bell scenarios with two binary observablesFeb 01 2012Jun 18 2012For the Bell scenario with two parties and two binary observables per party, it is known that the no-signaling polytope is the polyhedral dual (polar) of the Bell polytope. Computational evidence suggests that this duality also holds for three parties. ... More
Analytic vectors in continuous p-adic representationsNov 13 2007Oct 01 2012Given a compact p-adic Lie group G over a finite unramified extension L/Q_p let G_0 be the product over all Galois conjugates of G. We construct an exact and faithful functor from admissible G-Banach space representations to admissible locally L-analytic ... More
Stable flatness of nonarchimedean hyperenveloping algebrasJul 17 2008Dec 14 2012Let L be a p-adic local field and g a finite dimensional Lie algebra over L. We show that its hyperenveloping algebra F(g) is a stably flat completion of its universal enveloping algebra. As a consequence the relative cohomology for the locally convex ... More
Knot contact homology and open Gromov-Witten theoryNov 16 2017Knot contact homology studies symplectic and contact geometric properties of conormals of knots in 3-manifolds using holomorphic curve techniques. It has connections to both mathematical and physical theories. On the mathematical side, we review the theory, ... More
Antisymmetry of the stochastic order on all ordered metric spacesOct 16 2018In this short note, we prove that the stochastic order of Radon probability measures on any metric space is antisymmetric.
The fiber dimension of a graphJan 18 2016Graphs on integer points of polytopes whose edges come from a set of allowed differences are studied. It is shown that any simple graph can be embedded in that way. The minimal dimension of such a representation is the fiber dimension of the given graph. ... More
Stability results for local zeta functions of groups and related structuresApr 16 2015Various types of local zeta functions studied in asymptotic group theory admit two natural operations: (1) change the prime and (2) perform local base extensions. Often, the effects of both of these operations can be expressed simultaneously in terms ... More
Topological representation zeta functions of unipotent groupsMar 06 2015Inspired by work surrounding Igusa's local zeta function, we introduce topological representation zeta functions of unipotent algebraic groups over number fields. These group-theoretic invariants capture common features of established $p$-adic representation ... More
Hecke operators on period functions for $Γ_0(n)$Aug 23 2004May 23 2005Matrix representations of Hecke operators on classical holomorphical cusp forms and the corresponding period polynomials are well known. In this article we derive representations of Hecke operators for vector valued period functions for the congruence ... More
Hecke operators on period functions for the full modular groupJul 06 2004Feb 11 2005Matrix representations of Hecke operators on classical holomorphical cusp forms and corresponding period polynomials are well known. In this article we define Hecke operators on period functions and show that they correspond to the Hecke operators on ... More
An Improved Approximation Algorithm for the Traveling Salesman Problem with Relaxed Triangle InequalityDec 21 2014Given a complete edge-weighted graph G, we present a polynomial time algorithm to compute a degree-four-bounded spanning Eulerian subgraph of 2G that has at most 1.5 times the weight of an optimal TSP solution of G. Based on this algorithm and a novel ... More
Eigenvalue fluctuations for random regular graphsJun 26 2014One of the major themes of random matrix theory is that many asymptotic properties of traditionally studied distributions of random matrices are universal. We probe the edges of universality by studying the spectral properties of random regular graphs. ... More
Exchangeable pairs, switchings, and random regular graphsDec 04 2011Feb 17 2015We consider the distribution of cycle counts in a random regular graph, which is closely linked to the graph's spectral properties. We broaden the asymptotic regime in which the cycle counts are known to be approximately Poisson, and we give an explicit ... More
A Characterization of Effective Resistance MetricsOct 04 2017Jun 11 2018We produce a characterization of finite metric spaces which are given by the effective resistance of a graph. This characterization is applied to the more general context of resistance metrics defined by Kigami. A countably infinite resistance metric ... More
A Principled Approach to Grammars for Controlled Natural Languages and Predictive EditorsNov 15 2012Controlled natural languages (CNL) with a direct mapping to formal logic have been proposed to improve the usability of knowledge representation systems, query interfaces, and formal specifications. Predictive editors are a popular approach to solve the ... More
Codeco: A Grammar Notation for Controlled Natural Language in Predictive EditorsMar 29 2011Existing grammar frameworks do not work out particularly well for controlled natural languages (CNL), especially if they are to be used in predictive editors. I introduce in this paper a new grammar notation, called Codeco, which is designed specifically ... More
Status of SM calculations of b > s transitionsMar 21 2007May 22 2007We report recent progress in SM calculations of $b \to s$ transitions. We discuss the first NNLL prediction of the $\bar B \to X_s \gamma$ branching ratio, including important additional subtleties due to non-perturbative corrections and logarithmically-enhanced ... More
Equivariant spectral asymptotics for h-pseudodifferential operatorsNov 11 2013Dec 11 2014We prove equivariant spectral asymptotics for $ h$-pseudodifferential operators for compact orthogonal group actions generalizing results of El-Houakmi and Helffer (1991) and Cassanas (2006). Using recent results for certain oscillatory integrals with ... More
Nonabelian Gauge Symmetry in the Causal Epstein-Glaser ApproachNov 20 1995We present some generalizations of a recently proposed alternative approach to nonabelian gauge theories based on the causal Epstein-Glaser method in perturbative quantum field theory. Nonabelian gauge invariance is defined by a simple commutator relation ... More
Interpretation of charged Higgs effects in low energy flavour physicsApr 27 2011We discuss two-Higgs-doublet models in view of the present flavour data, in particular present indirect bounds and different techniques of flavour protection
Gluino-Mediated Rare B DecaysNov 10 1999We discuss the gluino-induced contribution to rare B decays in supersymmetric frameworks with generic sources of flavour change.
Differential 3-knots in 5-space with and without self intersectionsFeb 10 2000Regular homotopy classes of immersions of a 3-sphere in 5-space constitute an infinite cyclic group. The classes containing embeddings form a subgroup of index 24. The obstruction for a generic immersion to be regularly homotopic to an embedding is described ... More
KO-theory of complex flag varieties of ordinary typeFeb 02 2019We compute the topological Witt groups of every complex flag manifold of ordinary type, and thus the interesting (i.e. torsion) part of the KO-groups of these manifolds. Equivalently, we compute Balmer's Witt groups of each flag variety of ordinary type ... More
Excitations and correlations in the driven-dissipative Bose-Hubbard modelJan 29 2019Using a field-theoretic approach within the Schwinger-Keldysh formalism, we study a Bose-Hubbard model in the presence of a driving field and dissipation due to one-body losses. We recover the bistability diagram from the Gross-Pitaevski equation and ... More
Dynamically evolved community size and stability of random Lotka-Volterra ecosystemsAug 20 2018We use dynamical generating functionals to study the stability and size of communities evolving in Lotka-Volterra systems with random interaction coefficients. The size of the eco-system is not set from the beginning. Instead, we start from a set of possible ... More
A new all-sky map of Galactic high-velocity clouds from the 21-cm HI4PI surveyDec 04 2017High-velocity clouds (HVCs) are neutral or ionised gas clouds in the vicinity of the Milky Way that are characterised by high radial velocities inconsistent with participation in the regular rotation of the Galactic disc. Previous attempts to create a ... More
Hydrodynamic Coulomb drag and bounds on diffusionMay 01 2019We study Coulomb drag between an active layer with a clean electron liquid and a passive layer with a pinned electron lattice in the regime of fast intralayer equilibration. Such a two-fluid system offers an experimentally realizable way to disentangle ... More
Almost complex manifolds are (almost) complexMar 24 2019We analyze the differential relation corresponding to integrability of almost complex structures, reformulated as a directed immersion relation by Demailly and Gaussier. We prove that the relation has formal solutions up to complex dimension 77, and that, ... More
Homotopy (Pre-)Derivators of Cofibration Categories and Quasi-CategoriesDec 21 2017Apr 20 2018We prove that the homotopy prederivator of a cofibration category is equivalent to the homotopy prederivator of its associated quasi-category of frames, as introduced by Szumi\l{}o. We use this comparison result to deduce various abstract properties of ... More
Picard groups in $p$-adic Fourier theoryMar 27 2009Jun 25 2013Let $L$ be a proper finite extension of the field of $p$-adic numbers and let $o\subset L$ be its integers, viewed as an abelian locally $L$-analytic group. Let $\hat{o}$ be the rigid analytic group variety parametrizing the locally analytic characters ... More
On the Bloch-Kato conjecture for the Asai L-functionJul 02 2015Nov 28 2016Following Ribet's seminal 1976 paper there have been many results employing congruences between stable cuspforms and lifted forms to construct non-split extensions of Galois representations. We show how this strategy can be extended to construct elements ... More
Auslander Regularity of p-adic Distribution AlgebrasMar 15 2007Oct 01 2012Given a compact p-adic Lie group we show that its distribution algebra is Frechet-Stein with Auslander regular Banach algebras. As an application, we show that nonzero coadmissible modules coming from smooth or, more general, U(g)-finite representations ... More
A unified construction of semiring-homomorphic graph invariantsJan 04 2019Jan 22 2019It has recently been observed by Zuiddam that finite graphs form a preordered commutative semiring under the graph homomorphism preorder together with join and disjunctive product as addition and multiplication, respectively. This led to a new characterization ... More
Operator system structures on the unital direct sum of C*-algebrasNov 04 2010Feb 09 2012This work is motivated by Radulescu's result on the comparison of C*-tensor norms on C*(F_n) x C*(F_n). For unital C*-algebras A and B, there are natural inclusions of A and B into their unital free product, their maximal tensor product and their minimal ... More
Logarithms, constructible functions and integration on non-archimedean models of the theory of the real field with restricted analytic functions with value group of finite archimedean rankMar 01 2018Mar 13 2018Given a model of the theory of the real field with restricted analytic functions such that its value group has finite archimedean rank we show how one can extend the restricted logarithm to a global logarithm with values in the polynomial ring over the ... More
Energy identity for approximations of harmonic maps from surfacesMay 31 2007Sep 11 2008We prove the energy identity for min-max sequences of the Sacks-Uhlenbeck and the biharmonic approximation of harmonic maps from surfaces into general target manifolds. The proof relies on Hopf-differential type estimates for the two approximations and ... More
On the support of Pollicott-Ruelle resonant states for Anosov flowsNov 26 2015Sep 15 2016We show that all generalized Pollicott-Ruelle resonant states of a topologically transitiv $C^\infty$-Anosov flow with an arbitrary $C^\infty$ potential, have full support.
Piecewise Weierstraß preparation and division for o-minimal holomorphic functionsJun 08 2016Given an o-minimal structure expanding the field of reals, we show a piecewise Weierstra{\ss} preparation theorem and a piecewise Weierstra{\ss} division theorem for the ring of definable holomorphic functions. The numbers of pieces needed are determined ... More
Quantized Equations of Motion and Currents in Noncommutative TheoriesJan 20 2005We study quantized equations of motion and currents, that means equations on the level of Green's functions, in three different approaches to noncommutative quantum field theories. At first, the case of only spatial noncommutativity is investigated in ... More
Arithmetic Problems in Cubic and Quartic Function FieldsJul 08 2010One of the main themes in this thesis is the description of the signature of both the infinite place and the finite places in cubic function fields of any characteristic and quartic function fields of characteristic at least 5. For these purposes, we ... More
Nonlocality with less ComplementarityJun 20 2011Feb 01 2012In quantum mechanics, nonlocality (a violation of a Bell inequality) is intimately linked to complementarity, by which we mean that consistently assigning values to different observables at the same time is not possible. Nonlocality can only occur when ... More
Beyond Bell's Theorem: Correlation ScenariosJun 22 2012Sep 02 2012Bell's Theorem witnesses that the predictions of quantum theory cannot be reproduced by theories of local hidden variables in which observers can choose their measurements independently of the source. Working out an idea of Branciard, Rosset, Gisin and ... More
Instrument Control at the FRM-II using TACO and NICOSOct 20 2002Oct 22 2002At the new neutron source FRM--II in Garching, Germany, the TACO control system, originally developed at the ESRF in Grenoble, France is used for instrument control purposes. TACO provides an object oriented, distributed control system including a clearly ... More
New Physics Search in Flavour PhysicsNov 24 2005With the running B, kaon and neutrino physics experiments, flavour physics takes centre stage within today's particle physics. We discuss the opportunities offered by these experiments in our search for new physics beyond the SM and discuss their complementarity ... More
Present Status of Inclusive Rare B DecaysDec 19 2002Feb 05 2003We give a status report on inclusive rare B decays, highlighting recent developments and open problems. We focus on the decay modes $B \to X_{s,d} \gamma$, $ B \to X_s \ell^+\ell^-$ and $B \to X_s \nu \bar \nu$ and on their role in the search for new ... More