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Results for "Thomas Lachner"

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Hard topological versus soft geometrical magnetic particle transportJul 10 2019The transport on top of a periodic two-dimensional hexagonal magnetic pattern of (i) a single macroscopic steel sphere, (ii) a doublet of wax/magnetite composite spheres, and (iii) an immiscible mixture of ferrofluid droplets with a perfluorinated liquid ... More
Measurement of the stellar $^{58}$Ni$(n,γ)^{59}$Ni cross section with AMSFeb 10 2017The $^{58}$Ni$(n,\gamma)^{59}$Ni cross section was measured with a combination of the activation technique and accelerator mass spectrometry (AMS). The neutron activations were performed at the Karlsruhe 3.7 MV Van de Graaff accelerator using the quasi-stellar ... More
Search for long-lived isomeric states in neutron-deficient thorium isotopesJul 01 2009The discovery of naturally occurring long-lived isomeric states (t_1/2 > 10^8 yr) in the neutron-deficient isotopes 211,213,217,218Th [A. Marinov et al., Phys. Rev. C 76, 021303(R) (2007)] was reexamined using accelerator mass spectrometry (AMS). Because ... More
An optimization principle for the computation of MHD equilibria in the solar coronaDec 21 2006AIMS: We develop an optimization principle for computing stationary MHD equilibria. METHODS: Our code for the self-consistent computation of the coronal magnetic fields and the coronal plasma uses non-force-free MHD equilibria. Previous versions of the ... More
Probabilistic Reasoning about Actions in Nonmonotonic Causal TheoriesOct 19 2012We present the language {m P}{cal C}+ for probabilistic reasoning about actions, which is a generalization of the action language {cal C}+ that allows to deal with probabilistic as well as nondeterministic effects of actions. We define a formal semantics ... More
Elagage d'un perceptron multicouches : utilisation de l'analyse de la variance de la sensibilité des paramètresDec 04 2008The stucture determination of a neural network for the modelisation of a system remain the core of the problem. Within this framework, we propose a pruning algorithm of the network based on the use of the analysis of the sensitivity of the variance of ... More
Two-Variable Logic with Two Order RelationsOct 07 2011Mar 03 2012It is shown that the finite satisfiability problem for two-variable logic over structures with one total preorder relation, its induced successor relation, one linear order relation and some further unary relations is EXPSPACE-complete. Actually, EXPSPACE-completeness ... More
How deals with discrete data for the reduction of simulation models using neural networkJun 10 2009Simulation is useful for the evaluation of a Master Production/distribution Schedule (MPS). Also, the goal of this paper is the study of the design of a simulation model by reducing its complexity. According to theory of constraints, we want to build ... More
Spectral Correlations in the Crossover Transition from a Superposition of Harmonic Oscillators to the Gaussian Unitary EnsembleJul 20 1998We compute the spectral correlation functions for the transition from a harmonic oscillator towards the Gaussian Unitary Ensemble (GUE). We use a variant of the supersymmetry method to obtain analytical results in a fast and elegant way. In contrast to ... More
Thermodynamic formalism for transport coefficients with an application to the shear modulus and shear viscosityDec 07 2016We discuss Onsager's thermodynamic formalism for transport coefficients and apply it to the calculation of the shear modulus and shear viscosity of a monodisperse system of repulsive particles. We focus on the concept of extensive "distance" and intensive ... More
On the quantifier-free dynamic complexity of ReachabilityJun 13 2013Jan 28 2015The dynamic complexity of the reachability query is studied in the dynamic complexity framework of Patnaik and Immerman, restricted to quantifier-free update formulas. It is shown that, with this restriction, the reachability query cannot be dynamically ... More
Sélection de la structure d'un perceptron multicouches pour la réduction dun modèle de simulation d'une scierieDec 05 2008Simulation is often used to evaluate the relevance of a Directing Program of Production (PDP) or to evaluate its impact on detailed sc\'enarii of scheduling. Within this framework, we propose to reduce the complexity of a model of simulation by exploiting ... More
Infinite reduced words and the Tits boundary of a Coxeter groupJan 05 2013Sep 18 2014Let (W,S) be a finite rank Coxeter system with W infinite. We prove that the limit weak order on the blocks of infinite reduced words of W is encoded by the topology of the Tits boundary of the Davis complex X of W. We consider many special cases, including ... More
Extremal t processes: Elliptical domain of attraction and a spectral representationJul 10 2012Mar 25 2013The extremal t process was proposed in the literature for modeling spatial extremes within a copula framework based on the extreme value limit of elliptical t distributions (Davison, Padoan and Ribatet (2012)). A major drawback of this max-stable model ... More
Modeling asymptotically independent spatial extremes based on Laplace random fieldsJul 09 2015Mar 08 2016We tackle the modeling of threshold exceedances in asymptotically independent stochastic processes by constructions based on Laplace random fields. These are defined as Gaussian random fields scaled with a stochastic variable following an exponential ... More
Guarantees in Wasserstein Distance for the Langevin Monte Carlo AlgorithmFeb 08 2016Jul 01 2016We study the problem of sampling from a distribution $\target$ using the Langevin Monte Carlo algorithm and provide rate of convergences for this algorithm in terms of Wasserstein distance of order $2$. Our result holds as long as the continuous diffusion ... More
A Classical Realizability Model arising from a Stable Model of Untyped Lambda CalculusJul 06 2014Aug 03 2016We study a classical realizability model (in the sense of J.-L. Krivine) arising from a model of untyped lambda calculus in coherence spaces. We show that this model validates countable choice using bar recursion and bar induction.
Backpropagation of Hebbian plasticity for lifelong learningSep 08 2016Hebbian plasticity allows biological agents to learn from their lifetime experience, extending the fixed information provided by evolutionary search. Conversely, backpropagation methods can build high-performance fixed-weights networks, but are not currently ... More
Minimal Lagrangian connections on compact surfacesSep 26 2016We classify the torsion-free minimal Lagrangian connections on the tangent bundle of a compact oriented surface of non-vanishing Euler characteristic.
Ensemble teleportationApr 15 2004The possibility of teleportation is by sure the most interesting consequence of quantum non-separability. So far, however, teleportation schemes have been formulated by use of state vectors and considering individual entities only. In the present article ... More
Branch dependence in the "consistent histories" approach to quantum mechanicsJun 07 2005Nov 12 2006In the consistent histories formalism one specifies a family of histories as an exhaustive set of pairwise exclusive descriptions of the dynamics of a quantum system. We define branching families of histories, which strike a middle ground between the ... More
For principled model fitting in mathematical biologyApr 21 2014The mathematical models used to capture features of complex, biological systems are typically non-linear, meaning that there are no generally valid simple relationships between their outputs and the data that might be used to validate them. This invalidates ... More
Lie algebra solution of population models based on time-inhomogeneous Markov chainsNov 23 2011Many natural populations are well modelled through time-inhomogeneous stochastic processes. Such processes have been analysed in the physical sciences using a method based on Lie algebras, but this methodology is not widely used for models with ecological, ... More
The Laura++ Dalitz plot fitterMar 02 2016The Laura++ software package is designed for performing fits of amplitude models to data from decays of spin-0 particles into final states containing three spin-0 particles - so-called Dalitz-plot analysis. An overview of the amplitude formalism and its ... More
Numerical Chladni figuresAug 26 2013Chladni patterns of vibrating membranes or thin plates faszinated the people already in the eighteenth century. As a simple way to visualize acoustic phenomena it is a valuable experiment for beginners' courses. In this paper I present NumChladni, an ... More
Homological Descent for Motivic Homology TheoriesJan 30 2014We show that motivic homology, motivic Borel-Moore homology and higher Chow groups satisfy homological descent for hyperenvelopes, and l-hyperenvelopes after inverting l.
Rojtman's theorem for normal schemesFeb 08 2014Feb 25 2015We show that Rojtman's theorem holds for normal schemes: For any reduced normal scheme of finite type over an algebraically closed field, the torsion of the zero'th Suslin homology group agrees with the torsion of the albanese variety (the universal object ... More
A counterexample to the (unstable) Gromov-Lawson-Rosenberg conjectureMar 03 2004Doing surgery on the 5-torus, we construct a 5-dimensional closed spin-manifold M with $\pi_1(M) = Z^4times Z/3$, so that the index invariant in the KO-theory of the reduced $C^*$-algebra of $\pi_1(M)$ is zero. Then we use the theory of minimal surfaces ... More
Operator algebras and topologySep 13 2002These notes cover the contents of three survey lectures held at the ICTP Trieste Summer school on High dimensional manifold theory 2001. They introduce techniques coming from the theory of operator algebras. We will focus on the basic definitions and ... More
L2-index theorem for manifolds with boundaryOct 21 1998Suppose M is a compact manifold with boundary. Let N be a normal covering of M. Suppose (A,T) is an elliptic differential boundary value problem on M with lift (\tilde A,\tilde T) to N. Then the von Neumann dimension of kernel and cokernel of this lift ... More
A Canonical Representation of Data-Linear Visualization AlgorithmsDec 13 2014We introduce linear-state dataflows, a canonical model for a large set of visualization algorithms that we call data-linear visualizations. Our model defines a fixed dataflow architecture: partitioning and subpartitioning of input data, ordering, graphic ... More
Recent Investigations on AA DoradusNov 02 2011AA Dor is an eclipsing, post common-envelope binary with an sdOB-type primary and an unseen low-mass secondary, believed to be a brown dwarf. Eleven years ago, a NLTE spectral analysis of the primary showed a discrepancy with the surface gravity that ... More
Uncertainties in (E)UV model atmosphere fluxesFeb 13 2008During the comparison of synthetic spectra calculated with two NLTE model atmosphere codes, namely TMAP and TLUSTY, we encounter systematic differences in the EUV fluxes due to the treatment of level dissolution by pressure ionization. Systematic differences ... More
High-gravity central starsJul 11 2006NLTE spectral analyses of high-gravity central stars by means of state-of-the-art model atmosphere techniques provide information about the precursor AGB stars. The hydrogen-deficient post-AGB stars allow investigations on the intershell matter which ... More
The First Direct Supernova/GRB Connection: GRB 030329/SN 2003dhSep 29 2003Observations of gamma-ray burst (GRB) afterglows have yielded tantalizing hints that supernovae (SNe) and GRBs are related. The case had been circumstantial, though, relying on irregularities in the light curve or the colors of the afterglow. I will present ... More
Towards a Mori theory on compact Kähler threefolds, IIJul 08 1996This paper, a continuation of ``Towards a Mori theory on compact K\"ahler manifolds, 1'' (written with F. Campana), introduces a non-algebraic analogue to Mori theory in dimension 3.
On rings for which finitely generated ideals have only finitely many componentsJan 23 2006For a commutative ring R we investigate the property that the sets of minimal primes of finitely generated ideals of R is always finite. We prove this property passes to polynomial ring extensions (in an arbitrary number of variables) over R as well as ... More
The Theory of a Heliospheric EconomyMay 30 2015Despite more than 50 years of human space exploration, no paper in the field of economics has been published regarding the theory of a space-based economy. The aim of this paper is to develop quantitative techniques to estimate conditions of the human ... More
There are non homotopic framed homotopies of long knotsOct 23 2007Mar 10 2009Let $\mathcal {M}$ be the space of all, including singular, long knots in 3-space and for which a fixed projection into the plane is an immersion. Let $cl(\Sigma^{(1)}_{iness})$ be the closure of the union of all singular knots in $\mathcal {M}$ with ... More
Knot polynomials via one parameter knot theoryDec 05 2006Feb 06 2007We construct new knot polynomials. Let $V$ be the standard solid torus in 3-space and let $pr$ be its standard projection onto an annulus. Let $M$ be the space of all smooth oriented knots in $V$ such that the restriction of $pr$ is an immersion (e.g. ... More
Global knot theory in F^2 x RDec 12 2000We introduce a special class of knots, called global knots, in F^2 x R and we construct new isotopy invariants, called T-invariants, for global knots. Some T-invariants are of finite type but they cannot be extracted from the generalized Kontsevitch integral ... More
Comment on Gravity and the Poincare GroupFeb 11 1993Following the approach of Grignani and Nardelli [1], we show how to cast the two-dimensional model $L \sim curv^2 + torsion^2 + cosm.const$ -- and in fact any theory of gravity -- into the form of a Poincare gauge theory. By means of the above example ... More
Gravity from Lie algebroid morphismsOct 17 2003Inspired by the Poisson Sigma Model and its relation to 2d gravity, we consider models governing morphisms from TSigma to any Lie algebroid E, where Sigma is regarded as d-dimensional spacetime manifold. We address the question of minimal conditions to ... More
Frechet topologies on hypoelliptic sheavesJul 16 2007Jul 19 2007This note is withdrawn. The result and its proof are available in the literature.
A non-uniform distribution property of most orbits, in case the $3x+1$ conjecture is trueDec 18 2015Let $T(n)=\left\{\begin{array}{ll}3n+1&(n\hbox{ odd})\\\frac n2&(n\hbox{ even})\end{array}\right.$ ($n\in\mathbb Z$). We call "the orbit of the integer $n$", the set $$ \mathcal O_n:=\{m\in\mathbb Z\;:\;\exists k\ge0,\ m=T^k(n)\} $$ and we put $c_i(n):=\#\{m\in\mathcal ... More
Algebraic models for higher categoriesMar 06 2010May 30 2011We introduce the notion of algebraic fibrant objects in a general model category and establish a (combinatorial) model category structure on algebraic fibrant objects. Based on this construction we propose algebraic Kan complexes as an algebraic model ... More
Hadronic Loops versus Factorization in EFT calculations of $X(3872) \to χ_{cJ} π^0$Mar 09 2015Aug 14 2015We compare two existing approaches to calculating the decay of molecular quarkonium states to conventional quarkonia in effective field theory, using $X(3872) \to \chi_{cJ} \pi^0$ as an example. In one approach the decay of the molecular quarkonium proceeds ... More
A Review of Alexander Isaev's Spherical Tube HypersurfacesJan 12 2014Oct 15 2014As this is for the Bulletin of the A.M.S., it is not only a review of Alexander Isaev's Spherical Tube Hypersurfaces but also a brief introduction to CR geometry.
Towards Static Analysis of Functional Programs using Tree Automata CompletionOct 07 2014This paper presents the first step of a wider research effort to apply tree automata completion to the static analysis of functional programs. Tree Automata Completion is a family of techniques for computing or approximating the set of terms reachable ... More
Deformation quantization and the Gerstenhaber structure on the homology of knot spacesJun 23 2015It is well known that (in suitable codimension) the spaces of long knots in $\mathbb{R}^n$ modulo immersions are double loop spaces. Hence the homology carries a natural Gerstenhaber structure, given by the Gerstenhaber structure on the Hochschild homology ... More
The Homotopy Braces Formality MorphismSep 16 2011Oct 03 2015We extend M. Kontsevich's formality morphism to a homotopy braces morphism and to a homotopy Gerstenhaber morphism. We show that this morphism is homotopic to D. Tamarkin's formality morphism, obtained using formality of the little disks operad, if in ... More
M. Kontsevich's graph complex and the Grothendieck-Teichmueller Lie algebraSep 08 2010Dec 23 2013We show that the zeroth cohomology of M. Kontsevich's graph complex is isomorphic to the Grothendieck-Teichmueller Lie algebra grt_1. The map is explicitly described. This result has applications to deformation quantization and Duflo theory. We also compute ... More
Interdisciplinary application of nonlinear time series methodsJun 26 1998This paper reports on the application to field measurements of time series methods developed on the basis of the theory of deterministic chaos. The major difficulties are pointed out that arise when the data cannot be assumed to be purely deterministic ... More
On braided tensor categoriesFeb 03 1994We investigate invertible elements and gradings in braided tensor categories. This leads us to the definition of theta-, product-, subgrading and orbitcategories in order to construct new families of BTC's from given ones. We use the representation theory ... More
Uniqueness of the contact structure approximating a foliationFeb 22 2013May 20 2013According to a theorem of Eliashberg and Thurston a $C^2$-foliation on a closed 3-manifold can be $C^0$-approximated by contact structures unless all leaves of the foliation are spheres. Examples on the 3-torus show that every neighbourhood of a foliation ... More
A 64-dimensional two-distance counterexample to Borsuk's conjectureAug 01 2013Aug 20 2014In 1933 Karol Borsuk asked whether each bounded set in the n-dimensional Euclidean space can be divided into n+1 parts of smaller diameter. The diameter of a set is defined as the supremum (least upper bound) of the distances of contained points. Implicitly, ... More
New strongly regular graphs derived from the G2(4) graphSep 11 2014Jun 28 2016We consider simple loopless finite undirected graphs. Such a graph is called strongly regular with parameter set (v,k,l,m), for short a srg(v,k,l,m), iff it has exactly v vertices, each of them has exactly k neighbours, and the number of common neighbours ... More
On spaces with connected Higson coronasFeb 22 2016Apr 10 2016In this paper, we characterise metric spaces which have topologically connected Higson coronas. The characterisation is given by a natural categorical condition applied in the coarse category. We also give a characterisation in terms of coarse cohomology, ... More
Collective behaviours in the stock market -- A maximum entropy approachMar 20 2014Mar 21 2014Scale invariance, collective behaviours and structural reorganization are crucial for portfolio management (portfolio composition, hedging, alternative definition of risk, etc.). This lack of any characteristic scale and such elaborated behaviours find ... More
Market structure explained by pairwise interactionsOct 31 2012Jan 27 2014Financial markets are a typical example of complex systems where interactions between constituents lead to many remarkable features. Here, we show that a pairwise maximum entropy model (or auto-logistic model) is able to describe switches between ordered ... More
Status of QCDJul 13 2010Jul 28 2010In this talk, I review recent developments in perturbative QCD and their applications to collider physics.
Numerical tools to validate stationary points of SO(8)-gauged N=8 D=4 supergravityJul 05 2010Aug 31 2011Until recently, the preferred strategy to identify stationary points in the scalar potential of SO(8)-gauged N=8 supergravity in D=4 has been to consider truncations of the potential to sub-manifolds of E_{7(+7)}/SU(8) that are invariant under some postulated ... More
Bulk Witten Indices from D=10 Yang Mills IntegralsDec 22 2003Feb 23 2004Values for the bulk Witten indices for D=10 Yang-Mills integrals for some regular simple groups of rank 4 and 5 are calculated by employing the BRST deformation technique by Moore, Nekrasov and Shatashvili. The results cannot be reconciled with the double ... More
The Encyclopedic Reference of Critical Points for SO(8)-Gauged N=8 Supergravity Part 1: Cosmological Constants in the Range -Λ/g^2 \in [6;14.7)Sep 07 2011This article is part of a collection that strives to collect and provide in an unified form data about all the critical points on the scalar manifold of SO(8)-gauged N=8 supergravity in four dimensions known so far. The vast majority of these were obtained ... More
Fourteen new stationary points in the scalar potential of SO(8)-gauged N=8, D=4 supergravityDec 09 2009Aug 31 2011The list of six previously known nontrivial stationary points in the scalar potential of N=8, D=4 supergravity with gauge group SO(8) is extended by fourteen new entries, whose properties have been obtained numerically using the sensitivity backpropagation ... More
Recent developments from lattice QCDJan 19 2005This year lattice QCD has become very public. A new generation of simulations (including light dynamical quarks) have produced results which are in close agreement with many ``easy'' experimental quantities, and precise predictions for quantities which ... More
Lattice QCD and the CKM matrixAug 22 2000These lectures (given at TASI 2000) provide an introduction to lattice methods for nonperturbative studies of Quantum Chromodynamics. Lecture 1 (Ch. 2) is a very vanilla introduction to lattice QCD. Lecture 2 (Ch. 3) describes examples of recent lattice ... More
Lattice tests of beyond Standard Model dynamicsOct 16 2015Over the last few years lattice techniques have been used to investigate candidate theories of new physics beyond the Standard Model. This review gives a survey of results from these studies. Most of these investigations have been of systems of gauge ... More
Log-normal distribution for correlators in lattice QCD?Apr 20 2012Many hadronic correlators used in spectroscopy calculations in lattice QCD simulations appear to show a log-normal distribution at intermediate time separations.
Lattice QCD at the end of 2003Dec 17 2003I review recent developments in lattice QCD. I first give an overview of its formalism, and then discuss lattice discretizations of fermions. We then turn to a description of the quenched approximation and why it is disappearing as a vehicle for QCD phenomenology. ... More
Polarization and Spin Alignment in Multihadronic Z0 DecaysJan 25 2001Feb 13 2001The large statistics of millions of hadronic Z0 decays, accumulated by the four LEP experiments between 1989 and 1995, allowed for detailed investigations of the fragmentation process. Inclusive Lambda_b baryons and Lambda hyperons at intermediate and ... More
Applying Gödel's Dialectica Interpretation to Obtain a Constructive Proof of Higman's LemmaOct 11 2012We use G\"odel's Dialectica interpretation to analyse Nash-Williams' elegant but non-constructive "minimal bad sequence" proof of Higman's Lemma. The result is a concise constructive proof of the lemma (for arbitrary decidable well-quasi-orders) in which ... More
Convergence to pulsating traveling waves with minimal speed in some KPP heterogeneous problemsApr 03 2013The notion of traveling wave, which typically refers to some particular spatio-temporal con- nections between two stationary states (typically, entire solutions keeping the same profile's shape through time), is essential in the mathematical analysis ... More
Characterisation of an entanglement-free evolutionSep 21 2001Oct 02 2001Two or more quantum systems are said to be in an entangled or non-factorisable state if their joint (supposedly pure) wave-function is not expressible as a product of individual wave functions but is instead a superposition of product states. It is only ... More
Estimate of the weight of empty space based on astronomical observationsFeb 02 2013As a consequence of the equivalence principle and of the existence of a negative vacuum energy, we show how a weak but universal linear response of the vacuum to a local gravitational potential suffices to explain the main features of so-called Pioneer ... More
Experimental proposal for testing the Emergence of Environment Induced (EIN) Classical Selection rules with Biological SystemsMar 14 2010According to the so-called Quantum Darwinist approach, the emergence of "classical islands" from a quantum background is assumed to obey a (selection) principle of maximal information. We illustrate this idea by considering the coupling of two oscillators ... More
Crucial tests of the existence of a Time OperatorMar 14 2010In the present paper we show that the Temporal Wave Function approach of the decay process, which is a multicomponent version of the Time Operator approach leads to new, non-standard, predictions concerning the statistical properties of decay time distributions ... More
If 1=2+3, then 1=2.3: Bell states, finite groups, and mutually unbiased bases, a unifying approachJan 09 2004Jan 12 2004We study the relationship between Bell states, finite groups and complete sets of bases. We show how to obtain a set of N+1 bases in which Bell states are invariant. They generalize the X, Y and Z qubit bases and are associated to groups of unitary transformations ... More
The Emerging QCD Frontier: The Electron Ion ColliderMay 31 2008The self-interactions of gluons determine all the unique features of QCD and lead to a dominant abundance of gluons inside matter already at moderate $x$. Despite their dominant role, the properties of gluons remain largely unexplored. Tantalizing hints ... More
Strong-disorder magnetic quantum phase transitions: Status and new developmentsNov 28 2013Aug 25 2014This article reviews the unconventional effects of random disorder on magnetic quantum phase transitions, focusing on a number of new experimental and theoretical developments during the last three years. On the theory side, we address smeared quantum ... More
Quantum Griffiths effects and smeared phase transitions in metals: theory and experimentMay 15 2010Sep 27 2010In this paper, we review theoretical and experimental research on rare region effects at quantum phase transitions in disordered itinerant electron systems. After summarizing a few basic concepts about phase transitions in the presence of quenched randomness, ... More
Disorder-induced rounding of certain quantum phase transitionsDec 12 2002We study the influence of quenched disorder on quantum phase transitions in systems with over-damped dynamics. For Ising order parameter symmetry disorder destroys the sharp phase transition by rounding because a static order parameter can develop on ... More
Quantum phase transitions in electronic systemsNov 01 1999Dec 23 1999Quantum phase transitions occur at zero temperature when some non-thermal control-parameter like pressure or chemical composition is changed. They are driven by quantum rather than thermal fluctuations. In this review we first give a pedagogical introduction ... More
Neutrino Mixing from $Δ(6n^2)$ GroupsApr 30 2014Experimentally viable lepton mixing parameters can be predicted in so-called direct flavour models with Majorana neutrinos using $\Delta(6n^2)$ groups as a flavour group. In direct models, in which the flavour group is broken to a $Z_2\times Z_2$ subgroup ... More
The influence of galaxy mergers on the mass dispersion of brightest cluster galaxiesJun 17 2009The absolute magnitude of the brightest galaxy of clusters varies remarkably little and is nearly independent of all other physical properties of the cluster as, e.g., its spatial extension or its richness. The question arises whether the observed small ... More
Large density expansion of a hydrodynamic theory for self-propelled particlesJan 15 2015Recently, an Enskog-type kinetic theory for Vicsek-type models for self-propelled particles has been proposed [T. Ihle, Phys. Rev. E 83, 030901 (2011)]. This theory is based on an exact equation for a Markov chain in phase space and is not limited to ... More
New developments in special geometryFeb 17 2006We review recent developments in special geometry, emphasizing the role of real coordinates. In the first part we discuss the para-complex geometry of vector and hypermultiplets in rigid Euclidean N=2 supersymmetry. In the second part we study the variational ... More
Algebraic characterizations of measure algebrasDec 20 2006Dec 20 2006We present necessary and sufficient conditions for the existence of a countably additive measure on a complete Boolean algebra.
Moduli spaces of vector bundles over a real curve: Z/2-Betti numbersJul 20 2012Nov 05 2013Moduli spaces of real bundles over a real curve arise naturally as Lagrangian submanifolds of the moduli space of semi-stable bundles over a complex curve. In this paper, we adapt the methods of Atiyah-Bott's "Yang-Mills over a Riemann Surface" to compute ... More
Classifying spaces of twisted loop groupsDec 28 2013May 25 2015We study the classifying space of a twisted loop group $L_{\sigma}G$ where $G$ is a compact Lie group and $\sigma$ is an automorphism of $G$ of finite order modulo inner automorphisms. Equivalently, we study the $\sigma$-twisted adjoint action of $G$ ... More
Moduli of flat SU(3)-bundles over a Klein bottleJan 12 2009Dec 16 2009In this short note, we compute the Betti numbers of the moduli stack of flat SU(3)-bundles over a Klein bottle. We also handle the general compact group case over RP^2. In all cases the cohomology is found to be equivariantly formal, supporting a conjecture ... More
On the function describing the stellar initial mass functionDec 05 2012We propose a functional form for the IMF, the L_3 IMF, which is a natural heavy-tailed approximation to the log-normal distribution. It is composed of a low-mass power law and a high mass power-law which are smoothly joined together. Three parameters ... More
Approximating Bin Packing within O(log OPT * log log OPT) binsJan 17 2013Mar 10 2014For bin packing, the input consists of n items with sizes s_1,...,s_n in [0,1] which have to be assigned to a minimum number of bins of size 1. The seminal Karmarkar-Karp algorithm from '82 produces a solution with at most OPT + O(log^2 OPT) bins. We ... More
Linear nonequilibrium thermodynamics of periodic processes and chemical oscillationsAug 22 2016Onsager's phenomenological equations successfully describe irreversible thermodynamic processes. They assume a symmetric coupling matrix between thermodynamic fluxes and forces. It is easily shown that the antisymmetric part of a coupling matrix does ... More
QCD and High Energy Interactions: Moriond 2016 Theory SummaryJul 05 2016I summarize the theory talks presented at the 50 year anniversary conference. The talks covered a wide range of topics, but common threads included next-to-next-to-leading order predictions for many 2 -> 2 processes, beyond QCD lattice simulations, work ... More
Ordering as privileged informationJun 30 2016We propose to accelerate the rate of convergence of the pattern recognition task by directly minimizing the variance diameters of certain hypothesis spaces, which are critical quantities in fast-convergence results.We show that the variance diameters ... More
The uncertainty principle in terms of isoperimetric inequalitiesJun 25 2016Simultaneous measurements of position and momentum are considered in $n$ dimensions. We find, that for a particle whose position is strictly localized in a compact domain $D\subset \mathbb{R}^n$ (spatial uncertainty) with non-empty boundary, the standard ... More
Full Jet Reconstruction in d+Au and p+p Collisions at RHICMar 16 2004The STAR detector is well suited for investigating jet production at RHIC. It has a large acceptance for both charged particles and electromagnetic radiation, so that reconstructed jets contain a large fraction of the particles descending from an initial ... More
Ultracold gases far from equilibriumNov 28 2008Dec 02 2008Ultracold atomic quantum gases belong to the most exciting challenges of modern physics. Their theoretical description has drawn much from classical field equations. These mean-field approximations are in general reliable for dilute gases in which the ... More
Propagation of chaos for Hölder continuous interaction kernels via Glivenko-CantelliAug 09 2016We develop a new technique for establishing quantitative propagation of chaos for systems of interacting particles. Using this technique we prove propagation of chaos for diffusing particles whose interaction kernel is merely H\"older continuous, even ... More