Results for "David Schuster"

total 28509took 0.21s
High contrast qubit interactions using multimode cavity QEDFeb 27 2014Oct 22 2014We introduce a new multimode cavity QED architecture for superconducting circuits which can be used to implement photonic memories, more efficient Purcell filters, and quantum simulations of photonic materials. We show that qubit interactions mediated ... More
Engineering topological materials in microwave cavity arraysMay 10 2016We present a scalable architecture for the exploration of interacting topological phases of photons in arrays of microwave cavities, using established techniques from cavity and circuit quantum electrodynamics. A time-reversal symmetry breaking (non-reciprocal) ... More
An Autonomous Stabilizer for Incompressible Photon Fluids and SolidsJan 17 2017We suggest a simple approach to populate photonic quantum materials at non-zero chemical potential and near-zero temperature. Taking inspiration from forced evaporation in cold-atom experiments, the essential ingredients for our low-entropy thermal reservoir ... More
Quarter-Flux Hofstadter Lattice in Qubit-Compatible Microwave Cavity ArrayAug 04 2017Nov 14 2017Topological- and strongly-correlated- materials are exciting frontiers in condensed matter physics, married prominently in studies of the fractional quantum hall effect [1]. There is an active effort to develop synthetic materials where the microscopic ... More
Rank reduction of conformal blocksDec 12 2015Aug 03 2016Let $X$ be a smooth, pointed Riemann surface of genus zero, and $G$ a simple, simply-connected complex algebraic group. Associated to a finite number of weights of $G$ and a level is a vector space called the space of conformal blocks, and a vector bundle ... More
The combinatorial multitude of fatty acids can be described by Fibonacci numbersMar 28 2013The famous series of Fibonacci numbers is defined by a recursive equation saying that each number is the sum of its two predecessors, with the initial condition that the first two numbers are equal to unity. Here, we show that the numbers of fatty acids ... More
The Wyoming Survey for H-alpha. III. H-alpha Luminosity Functions at z ~ 0.16, 0.24, 0.32, and 0.40Mar 01 2010The Wyoming Survey for H-alpha, or WySH, is a large-area, ground-based imaging survey for H-alpha-emitting galaxies at redshifts of z ~ 0.16, 0.24, 0.32, and 0.40. The survey spans up to four square degrees in a set of fields of low Galactic cirrus emission, ... More
Supersymmetric Biorthogonal Quantum SystemsMar 20 2006Aug 26 2007We discuss supersymmetric biorthogonal systems, with emphasis given to the periodic solutions that occur at spectral singularities of PT symmetric models. For these periodic solutions, the dual functions are associated polynomials that obey inhomogeneous ... More
Optical Flow Requires Multiple Strategies (but only one network)Nov 17 2016We show that the matching problem that underlies optical flow requires multiple strategies, depending on the amount of image motion and other factors. We then study the implications of this observation on training a deep neural network for representing ... More
Topological PhotonicsFeb 12 2018Topological photonics is a rapidly-emerging field of research in which geometrical and topological ideas are exploited to design and control the behavior of light. Drawing inspiration from the discovery of the quantum Hall effects and topological insulators ... More
Minkowski Valuations and Generalized ValuationsJul 20 2015A convolution representation of continuous translation invariant and SO(n) equivariant Minkowski valuations is established. This is based on a new classification of translation invariant generalized spherical valuations. As applications, Crofton and kinematic ... More
New Abilities and Limitations of Spectral Graph BisectionJan 05 2017Apr 28 2017Spectral based heuristics belong to well-known commonly used methods which determines provably minimal graph bisection or outputs "fail" when the optimality cannot be certified. In this paper we focus on Boppana's algorithm which belongs to one of the ... More
Even Minkowski ValuationsNov 07 2014A new integral representation of smooth translation invariant and rotation equivariant even Minkowski valuations is established. Explicit formulas relating previously obtained descriptions of such valuations with the new more accessible one are also derived. ... More
A New Upper Bound for the Traveling Salesman Problem in Cubic GraphsJul 19 2012Nov 30 2012We provide a new upper bound for traveling salesman problem (TSP) in cubic graphs, i.e. graphs with maximum vertex degree three, and prove that the problem for an $n$-vertex graph can be solved in $O(1.2553^n)$ time and in linear space. We show that the ... More
Design and construction of an optical test bed for LISA imaging systems and tilt-to-length couplingJul 01 2016Dec 02 2016The Laser Interferometer Space Antenna (LISA) is a future space-based interferometric gravitational-wave detector consisting of three spacecraft in a triangular configuration. The interferometric measurements of path length changes between satellites ... More
Chromatic characteristic classes in ordinary group cohomologySep 04 2001We study a family of subrings, indexed by the natural numbers, of the mod-p cohomology of a finite group G. These subrings are based on a family of v_n-periodic complex oriented cohomology theories and are constructed as rings of generalised characteristic ... More
Time Reversal Invariant Topologically Insulating CircuitsSep 04 2013May 18 2015From studies of exotic quantum many-body phenomena to applications in spintronics and quantum information processing, topological materials are poised to revolutionize the condensed matter frontier and the landscape of modern materials science. Accordingly, ... More
Fabrication and characterization of superconducting circuit QED devices for quantum computationNov 28 2004We present fabrication and characterization procedures of devices for circuit quantum electrodynamics (cQED). We have made 3 GHz cavities with quality factors in the range 10^4--10^6, which allow access to the strong coupling regime of cQED. The cavities ... More
A modified algebraic reconstruction technique taking refraction into account with an application in terahertz tomographyJan 18 2016Terahertz (THz) tomography is a rather novel technique for nondestructive testing that is particularly suited for the testing of plastics and ceramics. Previous publications showed a large variety of conventional algorithms adapted from computed tomography ... More
Harmonic analysis of translation invariant valuationsAug 23 2010Mar 01 2011The decomposition of the space of continuous and translation invariant valuations into a sum of SO(n) irreducible subspaces is obtained. A reformulation of this result in terms of a Hadwiger type theorem for continuous translation invariant and SO(n)-equivariant ... More
Consistency of Importance Sampling estimates based on dependent sample sets and an application to models with factorizing likelihoodsMar 01 2015In this paper, I proof that Importance Sampling estimates based on dependent sample sets are consistent under certain conditions. This can be used to reduce variance in Bayesian Models with factorizing likelihoods, using sample sets that are much larger ... More
Gradient Importance SamplingJul 21 2015Adaptive Monte Carlo schemes developed over the last years usually seek to ensure ergodicity of the sampling process in line with MCMC tradition. This poses constraints on what is possible in terms of adaptation. In the general case ergodicity can only ... More
The Circumstellar Environments of NML Cyg and the Cool HypergiantsSep 30 2005We present high-resolution HST WFPC2 images of compact nebulosity surrounding the cool M-type hypergiants NML Cyg, VX Sgr and S Per. The powerful OH/IR source NML Cyg exhibits a peculiar bean-shaped asymmetric nebula that is coincident with the distribution ... More
Inter-Coder Agreement for Nominal Scales: A Model-based ApproachAug 06 2012Inter-coder agreement measures, like Cohen's kappa, correct the relative frequency of agreement between coders to account for agreement which simply occurs by chance. However, in some situations these measures exhibit behavior which make their values ... More
Understanding degenerate ground states of a protected quantum circuit in the presence of disorderFeb 28 2014A recent theoretical proposal suggests that a simple circuit utilizing two superinductors may produce a qubit with ground state degeneracy [P. Brooks et al., Phys. Rev. A 87, 052306 (2013)]. We perform a full circuit analysis along with exact diagonalization ... More
Hamiltonian Tomography of Photonic LatticesJul 18 2016In this letter we introduce a novel approach to Hamiltonian tomography of non-interacting tight-binding photonic lattices. To begin with, we prove that the matrix element of the low-energy effective Hamiltonian between sites $i$ and $j$ may be obtained ... More
Transport properties of copper phthalocyanine based organic electronic devicesMar 31 2010Ambipolar charge carrier transport in Copper phthalocyanine (CuPc) is studied experimentally in field-effect transistors and metal-insulator-semiconductor diodes at various temperatures. The electronic structure and the transport properties of CuPc attached ... More
On the Role of Quantum Events in Double-Slit ExperimentsMar 28 2010Apr 10 2011We formulate the Schr\"odinger equation as the equation of motion of a small external influence which serves as the initial boundary condition of a physical system in classical laboratory space. The Hilbert space of possible external influences for a ... More
On optimum left-to-right strategies for active context-free gamesDec 14 2012Active context-free games are two-player games on strings over finite alphabets with one player trying to rewrite the input string to match a target specification. These games have been investigated in the context of exchanging Active XML (AXML) data. ... More
The Pyramid Scheme: Oblivious RAM for Trusted ProcessorsDec 21 2017Modern processors, e.g., Intel SGX, allow applications to isolate secret code and data in encrypted memory regions called enclaves. While encryption effectively hides the contents of memory, the sequence of address references issued by the secret code ... More
Color ordering in QCDNov 25 2013We derive color decompositions of arbitrary tree and one-loop QCD amplitudes into color ordered objects called primitive amplitudes. Furthermore, we derive general fermion flip and reversion identities spanning the null space among the primitive amplitudes ... More
A Bayesian Model of node interaction in networksFeb 18 2014Mar 06 2015We are concerned with modeling the strength of links in networks by taking into account how often those links are used. Link usage is a strong indicator of how closely two nodes are related, but existing network models in Bayesian Statistics and Machine ... More
Observational evidence for a broken Li Spite plateau and mass-dependent Li depletionMay 17 2010We present NLTE Li abundances for 88 stars in the metallicity range -3.5 < [Fe/H] < -1.0. The effective temperatures are based on the infrared flux method with improved E(B-V) values obtained mostly from interstellar NaI D lines. The Li abundances were ... More
Maximal rank subgroups and strong functoriality of the additive eigenconeAug 22 2016Let $G$ be a simple connected complex Lie group. The additive eigencone of $G$ is a polyhedral cone containing the set of solutions to the additive eigenvalue problem, a generalization of the Hermitian eigenvalue problem. The additive eigencone is functorial, ... More
Global Properties of Nucleus-Nucleus CollisionsSep 15 2008In this lecture note, we discuss the global properties of nucleus-nucleus collisions. After a brief introduction to heavy-ion collisions, we introduce useful kinematics and then discuss the bulk hadron production in A+A collisions. At the end we discuss ... More
Transducer-based Rewriting Games for Active XMLJun 09 2016Context-free games are two-player rewriting games that are played on nested strings representing XML documents with embedded function symbols. These games were introduced to model rewriting processes for intensional documents in the Active XML framework, ... More
Hadron Formation and the Phase Diagram of QCD MatterNov 30 2009Jul 17 2013We investigate hadronic species freeze-out systematics in A+A collisions at low SPS energies, corresponding to a baryochemical potential above 300 MeV, analyzing NA49 hadron production data in the framework of the statistical hadronization model, and ... More
Doping Dependence of the Plasmon Dispersion in 2H-Tantalum-DiselenideApr 22 2013May 16 2013Inelastic electron scattering is applied to investigate the impact of potassium intercalation on the charge carrier plasmon energy and dispersion in the charge-density wave (CDW) bearing compound 2H-tantalum-diselenide. We observe an unususal doping dependence ... More
High p_T Spectra of Identified Particles Produced in Pb+Pb Collisions at 158GeV/nucleon Beam EnergyOct 18 2005Transverse momentum spectra of pi^{+/-}, p, pbar, K^{+/-}, K^0_s and Lambda at midrapidity were measured at high p_T in Pb+Pb collisions at 158GeV/nucleon beam energy by the NA49 experiment. Particle yield ratios (p/pi, K/pi and Lambda/K^0_s) show an ... More
On the energy dependence of $K/π$ fluctuations in relativistic heavy ion collisionsNov 06 2009In this note we will discuss the energy dependence of particle ratio fluctuations in heavy ion collisions. We study how the inherent multiplicity dependence of ratio fluctuations is reflected in the excitation function of the dynamical fluctuations. Specifically, ... More
Uniqueness and stability result for Cauchy's equation of motion for a certain class of hyperelastic materialsFeb 04 2014Feb 05 2014We consider Cauchy's equation of motion for hyperelastic materials. The solution of this nonlinear initial-boundary value problem is the vector field which discribes the displacement which a particle of this material perceives when exposed to stress and ... More
Some notes on the abstraction operation for Multi-Terminal Binary Decision DiagramsMar 25 2013Oct 31 2013The starting point of this work are inaccurate statements found in the literature for Multi-terminal Binary Decision Diagrams (MTBDDs) regarding the well-definedness of the MTBDD abstraction operation. The statements try to relate an operation * on a ... More
Grand Unification in Higher Dimensions with Split SupersymmetryDec 17 2004Mar 08 2005We investigate gauge coupling unification in higher dimensional GUT models with split supersymmetry. We focus on 5d and 6d orbifold GUTs, which permit a simple solution to several problems of 4D GUTs as well as control over GUT scale threshold corrections. ... More
The Production and Discovery of True Muonium in Fixed-Target ExperimentsJun 18 2012Upcoming fixed-target experiments designed to search for new sub-GeV forces will also have sensitivity to the never before observed True Muonium atom, a bound state of a muon and anti-muon. We describe the production and decay characteristics of True ... More
Markov Automata: Deciding Weak Bisimulation by means of non-naively Vanishing StatesMay 28 2012Apr 30 2014This paper develops a decision algorithm for weak bisimulation on Markov Automata (MA). For that purpose, different notions of vanishing state (a concept known from the area of Generalised Stochastic Petri Nets) are defined. Vanishing states are shown ... More
A CSP Field Theory with Helicity CorrespondenceApr 02 2014We propose the first covariant local action describing the propagation of a single free continuous-spin degree of freedom. The theory is simply formulated as a gauge theory in a "vector superspace", but can also be formulated in terms of a tower of symmetric ... More
Volume inequalities and additive maps of convex bodiesJul 31 2012Analogues of the classical inequalities from the Brunn-Minkowski theory for rotation intertwining additive maps of convex bodies are developed. Analogues are also proved of inequalities from the dual Brunn-Minkowski theory for intertwining additive maps ... More
High p_T Spectra of Identified Particles Produced in Pb+Pb Collisions at 158A GeV Beam EnergyJun 01 2006Jun 02 2006Results of the NA49 collaboration on the production of hadrons with large transverse momentum in Pb+Pb collisions at 158A GeV beam energy are presented. A range up to p_T = 4 GeV/c is covered. The nuclear modification factor R_CP is extracted for pions, ... More
Optical conductivity of a Hubbard ring with an impurityJul 02 2005We investigate the optical conductivity of a Hubbard ring in presence of an impurity by means of exact diagonalization using the Lanczos algorithm. We concentrate thereby on the first excited, open shell state, i.e. on twisted boundary conditions. In ... More
Crofton measures and Minkowski valuationsJul 31 2012A description of continuous rigid motion compatible Minkowski valuations is established. As an application, we present a Brunn-Minkowski type inequality for intrinsic volumes of these valuations.
On the linearization of identifying the stored energy function of a hyperelastic material from full knowledge of the displacement fieldNov 13 2015We consider the nonlinear,inverse problem of computing the stored energy function of a hyperelastic material from the full knowledge of the displacement field. The displacement field is described as solution of the nonlinear, dynamic, elastic wave equation, ... More
A New Class of Particle in 2+1 DimensionsApr 03 2014In two spatial dimensions, spin characterizes how particle states re-phase under changes of frame that leave their momentum and energy invariant. Massless particles can in principle have non-trivial spin in this sense, but all existing field theories ... More
Characterization of the scintillation anisotropy in crystalline stilbene scintillator detectorsJun 21 2016This paper reports a series of measurements that characterize the directional dependence of the scintillation response of crystalline melt-grown and solution-grown stilbene to incident DT and DD neutrons. These measurements give the amplitude and pulse ... More
Investigating the anisotropic scintillation response in anthracene through neutron, gamma-ray, and muon measurementsOct 31 2015This paper reports a series of measurements that characterize the directional dependence of the scintillation response of crystalline anthracene to incident DT neutrons, DD neutrons, Cs-137 gamma rays, and, for the first time, cosmic ray muons. The neutron ... More
Sequential subspace optimization for nonlinear inverse problemsFeb 22 2016In this work we discuss a method to adapt sequential subspace optimization (SESOP), which has so far been developed for linear inverse problems in Hilbert and Banach spaces, to the case of nonlinear inverse problems. We start by revising the well-known ... More
Hadronization and Hadronic Freeze-Out in Relativistic Nuclear CollisionsJan 30 2012Apr 12 2012We analyze hadrochemical freeze-out in central Pb+Pb collisions at CERN SPS energies, employing the hybrid version of the Ultrarelativistic Quantum Molecular Dynamics model, which describes the transition from a hydrodynamic stage to hadrons by the Cooper-Frye ... More
Hadron Formation in Relativistic Nuclear Collisions and the QCD Phase DiagramDec 11 2012Jul 31 2013We analyze hadrochemical freeze-out in central Pb+Pb collisions at CERN SPS and LHC energies. We determine the effects of baryon and antibaryon annihilation and/or regeneration occurring during the final cascade expansion stage of the collisions by deriving ... More
No Lee-Wick Fields out of GravityMar 23 2009Jun 12 2009We investigate the gravitational one-loop divergences of the standard model in large extra dimensions, with gravitons propagating in the (4+delta)-dimensional bulk and gauge fields as well as scalar and fermionic multiplets confined to a three-brane. ... More
Convolutions and multiplier transformations of convex bodiesJul 31 2012Rotation intertwining maps from the set of convex bodies in Rn into itself that are continuous linear operators with respect to Minkowski and Blaschke addition are investigated. The main focus is on Blaschke-Minkowski homomorphisms. We show that such ... More
An iterative method to reconstruct the refractive index of a medium from time-of-flight measurementsOct 23 2015The article deals with a classical inverse problem: the computation of the refractive index of a medium from ultrasound time-of-flight (TOF) measurements. This problem is very popular in seismics but also for tomographic problems in inhomogeneous media. ... More
A Gauge Field Theory of Continuous-Spin ParticlesFeb 13 2013Nov 01 2013We propose and quantize a local, covariant gauge-field action that unifies the description of all free helicity and continuous-spin degrees of freedom in a simple manner. This is the first field-theory action of any kind for continuous spin particles; ... More
On the Theory of Continuous-Spin Particles: Helicity Correspondence in Radiation and ForcesFeb 06 2013Nov 01 2013We have recently shown that continuous-spin particles (CSPs) have covariant single-emission amplitudes with the requisite properties to mediate long-range forces. CSPs, the most general massless particle type consistent with Lorentz symmetry, are characterized ... More
Games for Active XML RevisitedDec 18 2014The paper studies the rewriting mechanisms for intensional documents in the Active XML framework, abstracted in the form of active context-free games. The safe rewriting problem studied in this paper is to decide whether the first player, Juliet, has ... More
CCD $UBV(RI)_{C}$ Photometry of Twenty Open ClustersJun 16 2014Fundamental astrophysical parameters have been derived for 20 open clusters (O\!Cs) using CCD~$U\!BV\!(RI)_C$ photometric data observed with the 84~cm telescope at the San Pedro M\'artir National Astronomical Observatory, M\'exico. The interstellar reddenings, ... More
Avalanches in a Bose-Einstein condensateJun 19 2001May 09 2003Collisional avalanches are identified to be responsible for an 8-fold increase of the initial loss rate of a large 87-Rb condensate. We show that the collisional opacity of an ultra-cold gas exhibits a critical value. When exceeded, losses due to inelastic ... More
Gravitational Corrections to Yukawa and Phi^4 InteractionsAug 17 2009Feb 24 2010We consider the lowest order quantum gravitational corrections to Yukawa and Phi^4 interactions. Our results show that quantum gravity leads to contributions to the running coupling constants if the particles are massive and therefore alters the scaling ... More
Induction in Algebra: a First Case StudyAug 12 2013Sep 20 2013Many a concrete theorem of abstract algebra admits a short and elegant proof by contradiction but with Zorn's Lemma (ZL). A few of these theorems have recently turned out to follow in a direct and elementary way from the Principle of Open Induction distinguished ... More
Chance and Necessity in Evolution: Lessons from RNANov 18 1998The relationship between sequences and secondary structures or shapes in RNA exhibits robust statistical properties summarized by three notions: (1) the notion of a typical shape (that among all sequences of fixed length certain shapes are realized much ... More
A complete 12CO 2-1 map of M51 with HERAOct 15 2006The nearby, almost face-on, and interacting galaxy M51 offers an excellent opportunity to study the distribution of molecular gas and the mechanisms governing the star formation rate. We have created a complete map of M51 in 12CO 2-1 at a resolution of ... More
A complete 12CO 2-1 map of M51 with HERA: I. Radial averages of CO, HI, and radio continuumSep 25 2006The mechanisms governing the star formation rate in spiral galaxies are not yet clear. The nearby, almost face-on, and interacting galaxy M51 offers an excellent opportunity to study at high spatial resolutions the local star formation laws. In this first ... More
Constructing the Tree-Level Yang-Mills S-Matrix Using Complex FactorizationNov 20 2008A remarkable connection between BCFW recursion relations and constraints on the S-matrix was made by Benincasa and Cachazo in 0705.4305, who noted that mutual consistency of different BCFW constructions of four-particle amplitudes generates non-trivial ... More
On the Theory of Continuous-Spin Particles: Wavefunctions and Soft-Factor Scattering AmplitudesFeb 05 2013Nov 02 2013The most general massless particles allowed by Poincare-invariance are "continuous-spin" particles (CSPs) characterized by a scale \rho, which at \rho=0 reduce to familiar helicity particles. Though known long-range forces are adequately modeled using ... More
Lattice structures for bisimilar Probabilistic AutomataFeb 27 2014The paper shows that there is a deep structure on certain sets of bisimilar Probabilistic Automata (PA). The key prerequisite for these structures is a notion of compactness of PA. It is shown that compact bisimilar PA form lattices. These results are ... More
Prediction of galaxy ellipticities and reduction of shape noise in cosmic shear measurementsSep 18 2015The intrinsic scatter in the ellipticities of galaxies about the mean shape, known as "shape noise," is the most important source of noise in weak lensing shear measurements. Several approaches to reducing shape noise have recently been put forward, using ... More
CCD UBVRI Photometry of the Galactic open clusters: Be~89, Ru~135, and Be~10Aug 17 2010The fundamental parameters of reddening, metallicity, age, and distance are presented for the poorly studied open clusters Be~89, Ru~135, and Be~10, derived from their CCD UBVRI photometry. By fitting the appropriate isochrones to the observed sequences ... More
Subalgebras of group cohomology defined by infinite loop spacesDec 17 2001We study natural subalgebras Ch_E(G) of group cohomology defined in terms of infinite loop spaces E and give representation theoretic descriptions of those based on QS^0 and the Johnson-Wilson theories E(n). We describe the subalgebras arising from the ... More
Binary Operations in Spherical Convex GeometryJul 04 2014Characterizations of binary operations between convex bodies on the Euclidean unit sphere are established. The main result shows that the convex hull is essentially the only non-trivial projection covariant operation between pairs of convex bodies contained ... More
Searching for Light Dark Matter with the SLAC Millicharge ExperimentJul 25 2013New sub-GeV gauge forces ("dark photons") that kinetically mix with the photon provide a promising scenario for MeV-GeV dark matter, and are the subject of a program of searches at fixed-target and collider facilities around the world. In such models, ... More
Persistent Fine-Tuning in Supersymmetry and the NMSSMDec 15 2005We examine the use of modified Higgs sectors to address the little hierarchy problem of supersymmetry. Such models reduce weak-scale fine-tuning by allowing lighter stops, but they retain some fine-tuning independent of the Higgs. The modified Higgs sector ... More
A versatile method to generate multiple types of micropatternsOct 28 2015Nov 18 2015Micropatterning techniques have become an important tool for the study of cell behavior in controlled microenvironments. As a consequence, several approaches for the creation of micropatterns have been developed in recent years. However, the diversity ... More
The Sine Transform of Isotropic MeasuresJul 31 2012Sharp isoperimetric inequalities for the sine transform of even isotropic measures are established. The corresponding reverse inequalities are obtained in an asymptotically optimal form. These new inequalities have direct applications to strong volume ... More
On the GL(V)-module structure of K(n)^*(BV)Nov 30 2007We study the question of whether the Morava K-theory of the classifying space of an elementary abelian group V is a permutation module (in either of two distinct senses) for the automorphism group of V. We use Brauer characters and computer calculations. ... More
$1/f^α$ noise from self-organized critical models with uniform drivingOct 11 2000Using the well-known Olami-Feder-Christensen model as our paradigm, we show how to modify uniform driven self-organized critical models to generate $1/f^\alpha$ noise. Our model can reproduce all the main features of $1/f^\alpha$ noise: (1) $\alpha$ is ... More
General Lp affine isoperimetric inequalitiesSep 11 2008Sharp Lp affine isoperimetric inequalities are established for the entire class of Lp projection bodies and the entire class of Lp centroid bodies. These new inequalities strengthen the Lp Petty projection and the Lp Busemann--Petty centroid inequality. ... More
GL(n) contravariant Minkowski valuationsJul 31 2012A complete classification of all continuous GL(n) contravariant Minkowski valuations is established. As an application we present a family of sharp isoperimetric inequalities for such valuations which generalize the classical Petty projection inequality. ... More
Interpolation and Sampling on Riemann SurfacesOct 12 2003Nov 19 2004We find sufficient conditions for a discrete sequence to be interpolating or sampling for certain generalized Bergman spaces on open Riemann surfaces. As in previous work of Bendtsson, Ortega-Cerda, Seip, Wallsten and others, our conditions for interpolation ... More
Rotation equivariant Minkowski valuationsJul 31 2012The projection body operator \Pi, which associates with every convex body in Euclidean space Rn its projection body, is a continuous valuation, it is invariant under translations and equivariant under rotations. It is also well known that \Pi\ maps the ... More
Simple model for 1/f noiseJan 13 2002We present a simple stochastic mechanism which generates pulse trains exhibiting a power law distribution of the pulse intervals and a $1/f^\alpha$ power spectrum over several decades at low frequencies with $\alpha$ close to one. The essential ingredient ... More
A Minimal Model for Tag-based CooperationJul 17 2003Aug 15 2003Recently, Riolo et al. [R. L. Riolo et al., Nature 414, 441 (2001)] showed by computer simulations that cooperation can arise without reciprocity when agents donate only to partners who are sufficiently similar to themselves. One striking outcome of their ... More
The Steiner Formula for Minkowski ValuationsJul 31 2012A Steiner type formula for continuous translation invariant Minkowski valuations is established. In combination with a recent result on the symmetry of rigid motion invariant homogeneous bivaluations, this new Steiner type formula is used to obtain a ... More
Volume inequalities for asymmetric Wulff shapesOct 10 2011Oct 12 2011Sharp reverse affine isoperimetric inequalities for asymmetric Wulff shapes and their polars are established, along with the characterization of all extremals. These new inequalities have as special cases previously obtained simplex inequalities by Ball, ... More
Rotation invariant Minkowski classes of convex bodiesJul 31 2012A Minkowski class is a closed subset of the space of convex bodies in Euclidean space Rn which is closed under Minkowski addition and non-negative dilatations. A convex body in Rn is universal if the expansion of its support function in spherical harmonics ... More
Is Dark Matter Heavy Because of Electroweak Symmetry Breaking? Revisiting Heavy NeutrinosJun 08 2005Jun 09 2005A simple and well-motivated explanation for the origin of dark matter is that it consists of thermal relic particles that get their mass entirely through electroweak symmetry breaking. The simplest models implementing this possibility predict a dark matter ... More
Feshbach resonances in rubidium 87: Precision measurement and analysisOct 29 2002Dec 19 2002More than 40 Feshbach resonances in rubidium 87 are observed in the magnetic field range between 0.5 and 1260 G for various spin mixtures in the lower hyperfine ground state. The Feshbach resonances are observed by monitoring the atom loss, and their ... More
Hierarchical Crossover and Probability Landscapes of Genetic OperatorsApr 28 1995The time evolution of a simple model for crossover is discussed. A variant of this model with an improved exploration behavior in phase space is derived as a subset of standard one- and multi-point crossover operations. This model is solved analytically ... More
Feshbach spectroscopy and analysis of the interaction potentials of ultracold sodiumFeb 02 2011We have studied magnetic Feshbach resonances in an ultracold sample of Na prepared in the absolute hyperfine ground state. We report on the observation of three s-, eight d-, and three g-wave Feshbach resonances, including a more precise determination ... More
Temperature-dependent optical spectra of single-crystal (CH$_3$NH$_3$)PbBr$_3$ cleaved in ultrahigh vacuumOct 04 2016Nov 26 2016We measure temperature-dependent one-photon and two-photon induced photoluminescence from (CH3NH3)PbBr3 single crystals cleaved in ultrahigh vacuum. An approach is presented to extract absorption spectra from a comparison of both measurements. Cleaved ... More
Projection functions, area measures and the Alesker-Fourier transformAug 12 2016Dual to Koldobsky's notion of j-intersection bodies, the class of j-projection bodies is introduced, generalizing Minkowski's classical notion of projection bodies of convex bodies. A Fourier analytic characterization of j-projection bodies in terms of ... More
Coupling an ensemble of electrons on superfluid helium to a superconducting circuitAug 20 2015The quantized lateral motional states and the spin states of electrons trapped on the surface of superfluid helium have been proposed as basic building blocks of a scalable quantum computer. Circuit quantum electrodynamics (cQED) allows strong dipole ... More
The Effect of Charge Order on the Plasmon Dispersion in Transition-Metal DichalcogenidesJul 05 2011We investigate the dispersion of the charge carrier plasmon in the three prototypical charge-density wave bearing transition-metal dichalcogenides 2H-TaSe2, 2H-TaS2 and 2H-NbSe2 employing electron energy-loss spectroscopy. For all three compounds the ... More