Results for "Matthias Wenzel"

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Strong martingale type and uniform smoothnessJul 28 2004We introduce stronger versions of the usual notions of martingale type p <= 2 and cotype q >= 2 of a Banach space X and show that these concepts are equivalent to uniform p-smoothness and q-convexity, respectively. All these are metric concepts, so they ... More
Superreflexivity and J-convexity of Banach spacesOct 15 1997A Banach space X is superreflexive if each Banach space Y that is finitely representable in X is reflexive. Superreflexivity is known to be equivalent to J-convexity and to the non-existence of uniformly bounded factorizations of the summation operators ... More
A fermionic impurity in a dipolar quantum dropletJul 02 2018In this article we develop the framework to describe Bose-Fermi mixtures of magnetic atoms, focusing on the interaction of bosonic self-bound dipolar quantum droplets with a small number of fermions. We find an attractive interaction potential due to ... More
Non-Linear Transport through a Molecular NanojunctionNov 02 2000Dec 18 2001We present a simple model of electrical transport through a metal-molecule-metal nanojunction that includes charging effects as well as aspects of the electronic structure of the molecule. The interplay of a large charging energy and an asymmetry of the ... More
Photoassociation and coherent transient dynamics in the interaction of ultracold rubidium atoms with shaped femtosecond pulses - I. ExperimentMar 26 2009Apr 01 2009We experimentally investigate various processes present in the photoassociative interaction of an ultracold atomic sample with shaped femtosecond laser pulses. We demonstrate the photoassociation of pairs of rubidium atoms into electronically excited, ... More
Scratch iridescence: Wave-optical rendering of diffractive surface structureMay 17 2017The surface of metal, glass and plastic objects is often characterized by microscopic scratches caused by manufacturing and/or wear. A closer look onto such scratches reveals iridescent colors with a complex dependency on viewing and lighting conditions. ... More
Observing the Rosensweig instability of a quantum ferrofluidAug 20 2015Oct 08 2015Ferrofluids show unusual hydrodynamic effects due to the magnetic nature of their constituents. For increasing magnetization a classical ferrofluid undergoes a Rosensweig instability and creates self-organized ordered surface structures or droplet crystals. ... More
Observation of quantum droplets in a strongly dipolar Bose gasJan 13 2016Mar 18 2016Quantum fluctuations are the origin of genuine quantum many-body effects, and can be neglected in classical mean-field phenomena. Here we report on the observation of stable quantum droplets containing $\sim$ 800 atoms which are expected to collapse at ... More
Self-bound droplets of a dilute magnetic quantum liquidJul 25 2016Nov 10 2016Self-bound many-body systems are formed through a balance of attractive and repulsive forces and occur in many physical scenarios. Liquid droplets are an example of a self-bound system, formed by a balance of the mutual attractive and repulsive forces ... More
Self-bound droplets of a dilute magnetic quantum liquidJul 25 2016Self-bound many-body systems occur in different scenarios all across the fields of physics. For example in the astrophysical context the stellar classification is based on a detailed balance of attractive self-gravitating forces and repulsive terms e.g. ... More
Liquid quantum droplets of ultracold magnetic atomsSep 13 2016The simultaneous presence of two competing inter-particle interactions can lead to the emergence of new phenomena in a many-body system. Among others, such effects are expected in dipolar Bose-Einstein condensates, subject to dipole-dipole interaction ... More
Impressions of convexity - An illustration for commutator boundsApr 15 2010We determine the sharpest constant $C_{p,q,r}$ such that for all complex matrices $X$ and $Y$, and for Schatten $p$-, $q$- and $r$-norms the inequality $$ \|XY-YX\|_p\leq C_{p,q,r}\|X\|_q\|Y\|_r $$ is valid. The main theoretical tool in our investigations ... More
Onset of a modulational instability in trapped dipolar Bose-Einstein condensatesNov 20 2017Jan 23 2018We explore the phase diagram of a finite-sized dysprosium dipolar Bose-Einstein condensate in a cylindrical harmonic trap. We monitor the final state after the scattering length is lowered from the repulsive BEC regime to the quantum droplet regime. Either ... More
Semantic Label Reduction Techniques for Autonomous DrivingFeb 11 2019Semantic segmentation maps can be used as input to models for maneuvering the controls of a car. However, not all labels may be necessary for making the control decision. One would expect that certain labels such as road lanes or sidewalks would be more ... More
Anisotropic Superfluid Behavior of a Dipolar Bose-Einstein CondensateApr 12 2018Jul 18 2018We present transport measurements on a dipolar superfluid using a Bose-Einstein condensate of Dy-162 with strong magnetic dipole-dipole interactions. By moving an attractive laser beam through the condensate we observe an anisotropy in superfluid flow. ... More
Theoretical model for ultracold molecule formation via adaptive feedback controlApr 18 2006Jul 31 2006We investigate pump-dump photoassociation of ultracold molecules with amplitude- and phase-modulated femtosecond laser pulses. For this purpose a perturbative model for the light-matter interaction is developed and combined with a genetic algorithm for ... More
Transient supersolid properties in an array of dipolar quantum dropletsJan 23 2019We study theoretically and experimentally the emergence of supersolid properties in a dipolar Bose-Einstein condensate. The theory reveals a ground state phase diagram with three distinct regimes - a regular Bose-Einstein condensate, incoherent and coherent ... More
Scissors mode of dipolar quantum droplets of dysprosium atomsDec 19 2017Mar 25 2018We report on the observation of the scissors mode of a single dipolar quantum droplet. The existence of this mode is due to the breaking of the rotational symmetry by the dipole-dipole interaction, which is fixed along an external homogeneous magnetic ... More
Striped states in a many-body system of tilted dipolesJun 28 2017Nov 28 2017We study theoretically and experimentally the behaviour of a strongly confined dipolar Bose-Einstein condensate, in the regime of quantum-mechanical stabilization by beyond-mean-field effects. Theoretically, we demonstrate that self-organized striped ... More
Transient supersolid properties in an array of dipolar quantum dropletsJan 23 2019Mar 08 2019We study theoretically and experimentally the emergence of supersolid properties in a dipolar Bose-Einstein condensate. The theory reveals a ground state phase diagram with three distinct regimes - a regular Bose-Einstein condensate, incoherent and coherent ... More
Broad universal Feshbach resonances in the chaotic spectrum of Dysprosium atomsJun 05 2015Oct 12 2015We report on the observation of weakly-bound dimers of bosonic Dysprosium with a strong universal s-wave halo character, associated with broad magnetic Feshbach resonances. These states surprisingly decouple from the chaotic backgound of narrow resonances, ... More
READ-EVAL-PRINT in Parallel and Asynchronous Proof-checkingJul 08 2013The LCF tradition of interactive theorem proving, which was started by Milner in the 1970-ies, appears to be tied to the classic READ-EVAL-PRINT-LOOP of sequential and synchronous evaluation of prover commands. We break up this loop and retrofit the read-eval-print ... More
Real and complex operator idealsApr 12 1994The powerful concept of an operator ideal on the class of all Banach spaces makes sense in the real and in the complex case. In both settings we may, for example, consider compact, nuclear, or $2$--summing operators, where the definitions are adapted ... More
Isabelle/jEdit --- a Prover IDE within the PIDE frameworkJul 14 2012PIDE is a general framework for document-oriented prover interaction and integration, based on a bilingual architecture that combines ML and Scala. The overall aim is to connect LCF-style provers like Isabelle (or Coq or HOL) with sophisticated front-end ... More
PIDE as front-end technology for CoqApr 24 2013Isabelle/PIDE is the current Prover IDE technology for Isabelle. It has been developed in ML and Scala in the past 4-5 years for this particular proof assistant, but with an open mind towards other systems. PIDE is based on an asynchronous document model, ... More
Uniformly convex operators and martingale typeFeb 08 2002The concept of uniform convexity of a Banach space was generalized to linear operators between Banach spaces and studied by Beauzamy [1976]. Under this generalization, a Banach space X is uniformly convex if and only if its identity map I_X is. Pisier ... More
Ideal norms associated with the UMD-propertyOct 15 1997We prove the asymptotic equivalence of three sequences of ideal norms associated with the UMD-property of Banach spaces.
Ideal norms and trigonometric orthonormal systemsApr 12 1994In this article, we characterize the $UMD$--property of a Banach space $X$ by ideal norms associated with trigonometric orthonormal systems. The asymptotic behavior of that numerical parameters can be used to decide whether or not $X$ is a $UMD$--space. ... More
Basic aspects of high-power semiconductor laser simulationFeb 01 2013The aim of this paper is to review some of the models and solution techniques used in the simulation of high-power semiconductor lasers and to address open questions. We discuss some of the peculiarities in the description of the optical field of wide-aperture ... More
The UMD constants of the summation operatorsJul 28 2004The UMD property of a Banach space is one of the most useful properties when one thinks about possible applications. This is in particular due to the boundedness of the vector-valued Hilbert transform for functions with values in such a space. Looking ... More
Vector-valued Walsh-Paley martingales and geometry of Banach spacesAug 01 1995The concept of Rademacher type $p$ ($1\leq p\leq2$) plays an important role in the local theory of Banach spaces. In \cite{mas88} Mascioni considers a weakening of this concept and shows that for a Banach space $X$ weak Rademacher type $p$ implies Rademacher ... More
Mean Convergence of Vector--valued Walsh SeriesOct 30 1992Given any Banach space $X$, let $L_2^X$ denote the Banach space of all measurable functions $f:[0,1]\to X$ for which ||f||_2:=(int_0^1 ||f(t)||^2 dt)^{1/2} is finite. We show that $X$ is a UMD--space (see \cite{BUR:1986}) if and only if \lim_n||f-S_n(f)||_2=0 ... More
Towards Generalizing Sensorimotor Control Across Weather ConditionsJul 25 2019The ability of deep learning models to generalize well across different scenarios depends primarily on the quality and quantity of annotated data. Labeling large amounts of data for all possible scenarios that a model may encounter would not be feasible; ... More
The low-energy Goldstone mode in a trapped dipolar supersolidJun 11 2019A supersolid is a counter-intuitive state of matter that combines the frictionless flow of a superfluid with the crystal-like periodic density modulation of a solid. Since the first prediction in the 1950s, experimental efforts to realize this state have ... More
Isabelle technology for the Archive of Formal ProofsMay 17 2019This is an overview of the Isabelle technology behind the Archive of Formal Proofs (AFP). Interactive development and quasi-interactive build jobs impose significant demands of scalability on the logic (usually Isabelle/HOL), on Isabelle/ML for mathematical ... More
Isabelle/jEdit as IDE for Domain-specific Formal Languages and Informal Text DocumentsNov 27 2018Isabelle/jEdit is the main application of the Prover IDE (PIDE) framework and the default user-interface of Isabelle, but it is not limited to theorem proving. This paper explores possibilities to use it as a general IDE for formal languages that are ... More
System description: Isabelle/jEdit in 2014Oct 30 2014This is an updated system description for Isabelle/jEdit, according to the official release Isabelle2014 (August 2014). The following new PIDE concepts are explained: asynchronous print functions and document overlays, syntactic and semantic completion, ... More
Interaction with Formal Mathematical Documents in Isabelle/PIDEMay 05 2019Isabelle/PIDE has emerged over more than 10 years as the standard Prover IDE for interactive theorem proving in Isabelle. The well-established Archive of Formal Proofs (AFP) testifies the success of such applications of formalized mathematics in Isabelle/HOL. ... More
Isabelle technology for the Archive of Formal Proofs with application to MMTMay 17 2019Jun 11 2019This is an overview of the Isabelle technology behind the Archive of Formal Proofs (AFP). Interactive development and quasi-interactive build jobs impose significant demands of scalability on the logic (usually Isabelle/HOL), on Isabelle/ML for mathematical ... More
A supplement to my paper on real and complex operator idealsOct 15 1997We show that the main problem left open in Wenzel: "Real and complex operator ideals" (wenzelopidls.latex), can be solved using the Banach spaces $Z_\alpha$ recently constructed by Kalton: "An elementary example of a Banach space not isomorphic to its ... More
GN-Net: The Gauss-Newton Loss for Deep Direct SLAMApr 26 2019Direct methods for SLAM have shown exceptional performance on odometry tasks. However, they still suffer from dynamic lighting/weather changes and from a bad initialization on large baselines. To mitigate both of these effects, we propose an approach ... More
Reversible Jump Metropolis Light Transport using Inverse MappingsApr 22 2017We study Markov Chain Monte Carlo (MCMC) methods operating in primary sample space and their interactions with multiple sampling techniques. We observe that incorporating the sampling technique into the state of the Markov Chain, as done in Multiplexed ... More
Non-Equilibrium relation between mobility and diffusivity of interacting Brownian particles under shearNov 09 2009We investigate the relation between mobility and diffusivity for Brownian particles under steady shear near the glass transition, using mode coupling approximations. For the two directions perpendicular to the shear direction, the particle motion is diffusive ... More
Exclusive Radiative Higgs Decays as Probes of Light-Quark Yukawa CouplingsMay 14 2015Mar 29 2016We present a detailed analysis of the rare exclusive Higgs-boson decays into a single vector meson and a photon and investigate the possibility of using these processes to probe the light-quark Yukawa couplings. We work with an effective Lagrangian with ... More
Poisson--Voronoi approximationJun 23 2009Let $X$ be a Poisson point process and $K\subset\mathbb{R}^d$ a measurable set. Construct the Voronoi cells of all points $x\in X$ with respect to $X$, and denote by $v_X(K)$ the union of all Voronoi cells with nucleus in $K$. For $K$ a compact convex ... More
Central limit theorems for $U$-statistics of Poisson point processesApr 06 2011Dec 12 2013A $U$-statistic of a Poisson point process is defined as the sum $\sum f(x_1,\ldots,x_k)$ over all (possibly infinitely many) $k$-tuples of distinct points of the point process. Using the Malliavin calculus, the Wiener-It\^{o} chaos expansion of such ... More
A Comparison of X-ray and Strong Lensing Properties of Simulated X-ray ClustersMar 19 1996We use gas-dynamical simulations of galaxy clusters to compare their X-ray and strong lensing properties. Special emphasis is laid on mass estimates. The cluster masses range between 6 x 10^14 solar masses and 4 x 10^15 solar masses, and they are examined ... More
On the spin parameter of dark-matter haloesMar 10 1994The study by White (1984) on the growth of angular momentum in dark haloes is extended towards a more detailed investigation of the spin parameter $\lambda\equiv L\sqrt{E}/{G M^{2.5}}$. Starting from the Zel'dovich approximation to structure formation, ... More
Flow curves of dense colloidal dispersions: schematic model analysis of the shear-dependent viscosity near the colloidal glass transitionFeb 18 2005A recently proposed schematic model for the non--linear rheology of dense colloidal dispersions is compared to flow curves measured in suspensions that consist of thermosensitive particles. The volume fraction of this purely repulsive model system can ... More
Coherent control with shaped femtosecond laser pulses applied to ultracold moleculesSep 07 2005Nov 30 2005We report on coherent control of excitation processes of translationally ultracold rubidium dimers in a magneto-optical trap by using shaped femtosecond laser pulses. Evolution strategies are applied in a feedback loop in order to optimize the photoexcitation ... More
Quantum correlations in dilute dipolar quantum droplets beyond the extended Gross-Pitaevskii equationApr 23 2019Dipolar quantum droplets are exotic quantum objects that are self-bound due to the subtle balance of attraction, repulsion and quantum correlations. Here we present a systematic study of the critical atom number of these self-bound droplets, comparing ... More
In-silico folding of a three helix protein and characterization of its free-energy landscape in an all-atom forcefieldOct 29 2003We report the reproducible first-principles folding of the 40 amino acid, three-helix headpiece of the HIV accessory protein in a recently developed all-atom free-energy forcefield. Six of twenty simulations using an adapted basin-hopping method converged ... More
Optical variability of the supersoft source RX~J0019.8+2156Nov 29 1994We present a 100 yr optical lightcurve of the recently discovered supersoft X-ray source RX~J0019.8+2156 as deduced from photographic plates of Harvard and Sonneberg Observatory. Apart from the periodic orbital variations two different timescales of optical ... More
Structure of the Hilbert-space of the infinite-dimensional Hubbard modelOct 23 1998An iterative procedure for the explicit construction of the nontrivial subspace of all symmetry-adapted configurations with non-zero weight in the ground-state of the infinite-dimensional Hubbard model is developed on the basis of a symmetrized representation ... More
Higgs Measurements at a Muon ColliderApr 18 2013In light of the recent discovery of an approximately 126 GeV Higgs boson at the LHC, the particle physics community is beginning to explore the possibilities for a next-generation Higgs factory particle accelerator. In this report we study the s-channel ... More
A Qualitative Comparison of the Suitability of Four Theorem Provers for Basic Auction TheoryMar 18 2013May 23 2013Novel auction schemes are constantly being designed. Their design has significant consequences for the allocation of goods and the revenues generated. But how to tell whether a new design has the desired properties, such as efficiency, i.e. allocating ... More
Photoassociation and coherent transient dynamics in the interaction of ultracold rubidium atoms with shaped femtosecond pulses - II. TheoryMar 25 2009Apr 20 2009Photoassociation of ultracold rubidium atoms with femtosecond laser pulses is studied theoretically. The spectrum of the pulses is cut off in order to suppress pulse amplitude at and close to the atomic resonance frequency. This leads to long tails of ... More
Large N Matrix Field TheoriesApr 15 1999We discuss aspects of recent novel approaches towards understanding the large N limit of matrix field theories with local or global non-abelian symmetry.
Some directional microlocal classes defined using wavelet transformsOct 19 1995In this short paper we discuss how the position - scale half-space of wavelet analysis may be cut into different regions. We discuss conditions under which they are independent in the sense that the T\"oplitz operators associated with their characteristic ... More
Quark Orbital Angular Momentum and Final State InteractionsDec 09 2014Definitions of orbital angular momentum based on Wigner distributions are used to discuss the connection between the Ji definition of the quark orbital angular momentum and that of Jaffe and Manohar. The difference between these two definitions can be ... More
Next-to-Leading Order Corrections to Higgs Boson Pair Production in Gluon FusionAug 12 2016We present a calculation of the next-to-leading order QCD corrections to the production of Higgs boson pairs in gluon fusion keeping the full dependence on the mass of the top quark. The virtual corrections, involving two-loop integrals with up to four ... More
Finite temperature scaling close to Ising-nematic quantum critical points in two-dimensional metalsJun 02 2016We study finite temperature properties of metals close to an Ising-nematic quantum critical point in two spatial dimensions. In particular we show that at any finite temperature there is a regime where order parameter fluctuations are characterized by ... More
Divided Differences in Noncommutative Geometry: Rearrangement Lemma, Functional Calculus and Expansional FormulaMay 05 2014Jun 01 2015We state a generalization of the Connes-Tretkoff-Moscovici Rearrangement Lemma and give a surprisingly simple (almost trivial) proof of it. Secondly, we put on a firm ground the multivariable functional calculus used implicitly in the Rearrangement Lemma ... More
Intrinsic metrics on graphs: A surveyJul 28 2014Mar 24 2015A few years ago various disparities for Laplacians on graphs and manifolds were discovered. The corresponding results are mostly related to volume growth in the context of unbounded geometry. Indeed, these disparities can now be resolved by using so called ... More
On the spectral theory of operators on treesJan 15 2011We study a class of rooted trees with a substitution type structure. These trees are not necessarily regular, but exhibit a lot of symmetries. We consider nearest neighbor operators which reflect the symmetries of the trees. The spectrum of such operators ... More
Tendencies toward nematic order in YBa2Cu3O6+x: Uniform distortion vs. incipient charge stripesJul 22 2010Recent neutron scattering and transport data obtained on underdoped YBCO, with strong signatures of rotation symmetry breaking at low temperatures, point toward electron-nematic order in the charge sector. Such order may originate from a uniform distortion ... More
Spin polarons in triangular antiferromagnetsNov 13 1998The motion of a single hole in a 2D triangular antiferromagnet is investigated using the t-J model. The one-hole states are described by strings of spin deviations around the hole. Using projection technique the one-hole spectral function is calculated. ... More
Unparticle Physics with JetsJul 31 2007Jan 22 2008Using methods of effective field theory, we show that after resummation of Sudakov logarithms the spectral densities of interacting quark and gluon fields in ordinary quantum field theories such as QCD are virtually indistinguishable from those of "unparticles" ... More
Factorization analysis for the fragmentation functions of hadrons containing a heavy quarkJun 14 2007Using methods of effective field theory, a systematic analysis of the fragmentation functions D_{a/H}(x,m_Q) of a hadron H containing a heavy quark Q is performed (with a=Q,Q_bar,q,q_bar,g). By integrating out pair production of virtual and real heavy ... More
Effective Field Theory and Heavy Quark PhysicsDec 17 2005These notes are based on five lectures presented at the 2004 Theoretical Advanced Study Institute (TASI) on ``Physics in D>=4''. After a brief motivation of flavor physics, they provide a pedagogical introduction to effective field theory, the effective ... More
Advanced Predictions for Moments of the B->X_s+gamma Photon SpectrumJun 24 2005Sep 23 2005Based on a new, exact QCD factorization formula for the partial B->X_s+gamma decay rate with a restriction on large photon energy, improved predictions are presented for the partial moments <E_gamma> and <E_gamma^2>-<E_gamma>^2 of the photon spectrum ... More
Aspects of QCD FactorizationOct 05 2001The QCD factorization approach provides the theoretical basis for a systematic analysis of nonleptonic decay amplitudes of B mesons in the heavy-quark limit. After recalling the basic ideas underlying this formalism, several tests of QCD factorization ... More
Applications of QCD Factorization in Hadronic B DecaysAug 08 2000We review recent advances in the theory of strong-interaction effects and final-state interactions in hadronic weak decays of heavy mesons. In the heavy-quark limit, the amplitudes for most nonleptonic, two-body B decays can be calculated from first principles ... More
Rescattering Effects, Isospin Relations and Electroweak Penguins in B -> pi K DecaysDec 01 1997Dec 02 1997It is argued that, in the presence of soft final-state interactions, the diagrammatic amplitude approach adopted in many analyses of hadronic B decays into light mesons can be misleading when used to deduce the unimportance of certain decay topologies. ... More
QCD Sum-Rule Calculation of the Kinetic Energy and Chromo-Interaction of Heavy Quarks Inside MesonsAug 02 1996We present a QCD sum-rule determination of the heavy-quark kinetic energy inside a heavy meson, $-\lambda_1/2 m_Q$, which is consistent with the field-theory analog of the virial theorem. We obtain $-\lambda_1\approx (0.10\pm 0.05)~\mbox{GeV}^2$, significantly ... More
Resummation of Renormalon Chains for Cross Sections and Inclusive Decay RatesFeb 09 1995Apr 25 1995Recently, we have developed a formalism to evaluate QCD loop diagrams with a single virtual gluon using a running coupling constant at the vertices. This corresponds to an all-order resummation of certain terms (the so-called renormalon chains) in a perturbative ... More
Two-body modes of B mesons and the CP-b triangleJul 26 2002The study of charmless two-body decays of B mesons is currently one of the hottest topics in B physics. QCD factorization provides the theoretical framework for a systematic analysis of such decays. A global fit to B->pi K,pi pi branching fractions, combined ... More
Note on the Extraction of |V_{ub}| using Radiative B DecaysApr 26 2001Jun 08 2001The element |V_{ub}| of the quark mixing matrix can be extracted with small theoretical uncertainties by combining weighted integrals over the endpoint regions of the lepton spectrum in B -> X_u l nu decays and the photon spectrum in B -> X_s gamma decays. ... More
Enhanced Gluino Box Contribution to epsilon'/epsilon in SUSYNov 04 2000We show that in supersymmetric extensions of the Standard Model gluino box diagrams can yield a large CP-violating Delta(I)=3/2 contribution to s->d+q(bar)+q flavor-changing neutral current processes, which feeds into the I=2 isospin amplitude in K->pi+pi ... More
Introduction to B PhysicsJan 31 2000These lectures provide an introduction to various topics in heavy-flavor physics. We review the theory and phenomenology of heavy-quark symmetry, exclusive weak decays of $B$ mesons, inclusive decay rates, and some rare $B$ decays.
Theoretical Status of B -> Xs gamma DecaysSep 14 1998We review the theoretical understanding of the branching ratio and photon-energy spectrum in B -> Xs gamma decays at next-to-leading order in QCD, including consistently the effects of Fermi motion. For the Standard Model, we obtain B(B -> Xs gamma)=(3.29 ... More
Heavy-Quark Effective TheoryOct 17 1996We give an introduction to the heavy-quark effective theory and the $1/m_Q$ expansion, which provide the modern framework for a systematic, model-independent description of the properties and decays of hadrons containing a heavy quark. We discuss the ... More
Analysis of the Photon Spectrum in Inclusive $B\to X_s\,γ$ DecaysDec 20 1993Jan 18 1994Using a combination of the operator product and heavy quark expansions, we resum the leading nonperturbative contributions to the inclusive photon spectrum in $B\to X_s\,\gamma$ decays. The shape of the spectrum is determined by a universal structure ... More
Short-Distance Expansion of Heavy-Light Currents at Order 1/mAug 31 1993The short-distance expansion of the heavy-light currents $\bar q\,\gamma^\mu Q$ and $\bar q\,\gamma^\mu\gamma_5\,Q$ is constructed to order $1/m_Q$, and to next-to-leading order in renormalization-group improved perturbation theory. It is shown that the ... More
Heavy Hadron Weak Decay Form Factors to Next-to-Leading Order in 1/mJul 03 1993Based on the short-distance expansion of currents in the heavy quark effective theory, we derive the exact expressions for the heavy-to-heavy meson and baryon weak decay form factors to order $1/m_Q$ in the heavy quark expansion, and to all orders in ... More
Two-loop corrections to the Isgur-Wise function in QCD sum rulesNov 24 1992We complete the QCD sum rule analysis of the Isgur Wise form factor $\xi(v\cdot v')$ at next-to-leading order in renormalization-group improved perturbation theory. To this end, the exact result for the two-loop corrections to the perturbative contribution ... More
Two-Loop Relations for Heavy-Quark Parameters in the Shape-Function SchemeDec 16 2004Mar 04 2005Moments of the renormalized B-meson shape function provide a natural way to define short-distance, running heavy-quark parameters such as the b-quark mass and kinetic energy. These parameters are particularly well suited for studies of inclusive decay ... More
Soft-Collinear Factorization and the Calculation of the B->Xs+gamma RateAug 18 2004Using results on soft-collinear factorization for inclusive B-meson decay distributions, a systematic study of the partial B->Xs+gamma decay rate with a cut E_gamma<E_0 on photon energy is performed. For values E_0<1.9 GeV the rate can be calculated without ... More
Higher-Order Singularities without Glass-Glass TransitionsFeb 04 2010Within the framework of mode-coupling theory, the glass-transition scenario is investigated for a system of particles interacting with a hard-core repulsion and an additional square-shoulder soft core at larger distances. The static structure is calculated ... More
Logarithmic decay in a two-component modelOct 31 2003The correlation functions near higher-order glass-transition singularities are discussed for a schematic two-component model within the mode-coupling theory for ideal glass-transitions. The correlators decay in leading order like $-\ln(t/\tau)$ and the ... More
Model-independent information on gamma from B^+- -> pi K DecaysSep 30 1999Measurements of the rates for the hadronic decays B^+- -> pi K can be used to derive information on the weak phase gamma=arg(V_ub^*) in a largely model-independent way. Hadronic uncertainties can be reduced to the level of nonfactorizable contributions ... More
Three-loop vertex correctionsJan 18 2010We describe recent evaluations of three-loop vertex corrections which have been performed in the context of different physical applications: the massless quark and gluon form factor, the vector current matching coefficient between QCD and NRQCD, and the ... More
Corrections of O(α_s^2) to the Decay of an Intermediate-Mass Higgs Boson into Two PhotonsDec 18 1996The QCD correction of $O(\alpha_s^2)$ to the decay of the Standard Model Higgs boson into two photons is presented. We consider the contribution coming from diagrams with a heavy top quark as virtual particle. The first three terms of the expansion in ... More
Exploring the Weak Phase gamma in B^+- -> pi K DecaysApr 13 1999Measurements of the rates for the hadronic decays B^+- -> pi K along with the CP-averaged B^+- -> pi^+- pi^0 branching ratio can be used to bound and extract the weak phase gamma=-arg(V_ub). Using preliminary CLEO data, we obtain the bounds |gamma|>93 ... More
Analytic Expressions for Singular Vectors of the $N=2$ Superconformal AlgebraJan 11 1996Using explicit expressions for a class of singular vectors of the $N=2$ (untwisted) algebra and following the approach of Malikov-Feigin-Fuchs and Kent, we show that the analytically extended Verma modules contain two linearly independent neutral singular ... More
On Computing the Minkowski Difference of ZonotopesDec 09 2015Zonotopes are becoming an increasingly popular set representation for formal verification techniques. This is mainly due to their efficient representation and the favorable computational complexity of important operations in high-dimensional spaces. In ... More
The leading two loop counterterm in the nonleptonic weak sector of CHPTApr 20 2005Nov 07 2005We calculate the leading divergences at NNLO for the octet part of the nonleptonic weak sector of chiral perturbation theory, using renormalization group methods. The role of counterterms which vanish at the equation of motion and their use to simplify ... More
Vector Fields with a non-degenerate SourceAug 16 2013Jan 17 2014We discuss the solution theory of operators of the form $\nabla_X + A$, acting on smooth sections of a vector bundle with connection $\nabla$ over a manifold $M$, where $X$ is a vector field having a critical point with positive linearization at some ... More
New Covert Channels in HTTPApr 26 2004This paper presents new methods enabling anonymous communication on the Internet. We describe a new protocol that allows us to create an anonymous overlay network by exploiting the web browsing activities of regular users. We show that the overlay network ... More
Wedge Local Deformations of Charged Fields leading to Anyonic Commutation RelationsAug 30 2012Jan 21 2013The method of deforming free fields by using multiplication operators on Fock space, introduced by G. Lechner in [11], is generalized to a charged free field on two- and three-dimensional Minkowski space. In this case the deformation function can be chosen ... More