Results for "Michael J. P. Morse"

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Large-$η$ Constant-Roll Inflation Is Never An AttractorApr 05 2018Apr 25 2018Slow roll solutions to inflationary potentials have been widely believed to be the only universal attractor. Over the last few years there has been growing interest in a new class of inflationary models known as Constant-Roll Inflation. Constant roll ... More
Dynamical Analysis of Attractor Behavior in Constant Roll InflationApr 12 2019There has been considerable recent interest in a new class of non-slow roll inflationary solutions known as \textit{constant roll} inflation. Constant roll solutions are a generalization of the ultra-slow roll (USR) solution, where the first Hubble slow ... More
Phantom Dirac-Born-Infeld Dark EnergyOct 12 2017Mar 09 2018Motivated by the apparent discrepancy between Cosmic Microwave Background measurements of the Hubble constant and measurements from Type-Ia supernovae, we construct a model for Dark Energy with equation of state $w = p / \rho < -1$, violating the Null ... More
Dynamical Analysis of Attractor Behavior in Constant Roll InflationApr 12 2019May 29 2019There has been considerable recent interest in a new class of non-slow roll inflationary solutions known as \textit{constant roll} inflation. Constant roll solutions are a generalization of the ultra-slow roll (USR) solution, where the first Hubble slow ... More
Collimation, Proper Motions, and Physical Conditions in the HH 30 Jet From HST Slitless SpectroscopyJan 20 2007We present Space Telescope Imaging Spectrograph (STIS) spectral images of the HH~30 stellar jet taken through a wide slit over two epochs. The jet is unresolved spectrally, so the observations produce emission-line images for each line in the spectrum. ... More
Proper Motions of the HH 47 Jet Observed with the Hubble Space TelescopeJul 22 2005We present a proper motion study of the shock waves within the classic stellar jet HH 47 based on Hubble Space Telescope H-alpha and [S II] images of the region taken over two epochs. Individual knots within the jet and in the bow shock/Mach disk working ... More
Accelerator performance analysis of the Fermilab Muon CampusMar 01 2018Fermilab is dedicated to hosting world-class experiments in search of new physics that will operate in the coming years. The Muon g-2 Experiment is one such experiment that will determine with unprecedented precision the muon anomalous magnetic moment, ... More
Quantum cohomology and the k-Schur basisJan 28 2005May 27 2005We prove that structure constants related to Hecke algebras at roots of unity are special cases of k-Littlewood-Richardson coefficients associated to a product of k-Schur functions. As a consequence, both the 3-point Gromov-Witten invariants appearing ... More
Schur function identities, their t-analogs, and k-Schur irreducibilityNov 17 2001We obtain general identities for the product of two Schur functions in the case where one of the functions is indexed by a rectangular partition, and give their t-analogs using vertex operators. We study subspaces forming a filtration for the symmetric ... More
Schur function analogs for a filtration of the symmetric function spaceNov 17 2001We consider a filtration of the symmetric function space given by $\Lambda^{(k)}_t$, the linear span of Hall-Littlewood polynomials indexed by partitions whose first part is not larger than $k$. We introduce symmetric functions called the $k$-Schur functions, ... More
Tableaux on k+1-cores, reduced words for affine permutations, and k-Schur expansionsFeb 19 2004The $k$-Young lattice $Y^k$ is a partial order on partitions with no part larger than $k$. This weak subposet of the Young lattice originated from the study of the $k$-Schur functions(atoms) $s_\lambda^{(k)}$, symmetric functions that form a natural basis ... More
Tableaux statistics for two part Macdonald polynomialsDec 01 1998The Macdonald polynomials expanded in terms of a modified Schur function basis have coefficients called the $q,t$-Kostka polynomials. We define operators to build standard tableaux and show that they are equivalent to creation operators that recursively ... More
The MINOS Light Injection Calibration SystemApr 17 2002A description is given of the light-injection calibration system that has been developed for the MINOS long-baseline neutrino oscillation experiment. The system is based upon pulsed blue LEDs monitored by PIN photodiodes. It is designed to measure non-linearities ... More
The ABC's of affine Grassmannians and Hall-Littlewood polynomialsMay 18 2016We give a new description of the Pieri rule for k-Schur functions using the Bruhat order on the affine type-A Weyl group. In doing so, we prove a new combinatorial formula for representatives of the Schubert classes for the cohomology of affine Grassmannians. ... More
A t-generalization for Schubert Representatives of the Affine GrassmannianMay 16 2016We introduce two families of symmetric functions with an extra parameter t that specialize to Schubert representatives for cohomology and homology of the affine Grassmannian when t = 1. The families are defined by a statistic on combinatorial objects ... More
Quantum and affine Schubert calculus and Macdonald polynomialsFeb 06 2014We definitively establish that the theory of symmetric Macdonald polynomials aligns with quantum and affine Schubert calculus using a discovery that distinguished weak chains can be identified by chains in the strong (Bruhat) order poset on the type-$A$ ... More
FUV and X-ray Observations of the Reverse Shock in the SMC SNR 1E 0102.2-7219Feb 04 2006We present FUSE and XMM-Newton data for the reverse shock of the O-rich SNR 1E0102.2-7219 in the SMC. The FUSE observations cover three regions with significantly different optical [O III] intensities, all associated with the relatively bright part of ... More
Tableau atoms and a new Macdonald positivity conjectureAug 09 2000Nov 17 2001Let $\Lambda$ be the space of symmetric functions and $V_k$ be the subspace spanned by the modified Schur functions $\{S_\lambda[X/(1-t)]\}_{\lambda_1\leq k}$. We introduce a new family of symmetric polynomials, $\{A_{\lambda}^{(k)}[X;t]\}_{\lambda_1\leq ... More
Determinantal expressions for Macdonald polynomialsAug 11 1998We show that the action of classical operators associated to the Macdonald polynomials on the basis of Schur functions, S_{\lambda}[X(t-1)/(q-1)], can be reduced to addition in \lambda-rings. This provides explicit formulas for the Macdonald polynomials ... More
A photonic platform for donor spin qubits in siliconJun 10 2016Donor impurity spins in silicon-28 are highly competitive qubits for upcoming solid-state quantum technologies, yet a proven scalable strategy for multi-qubit devices remains conspicuously absent. These CMOS-compatible, atomically identical qubits offer ... More
Comparisons of the MINOS Near and Far Detector Readout Systems at a Test BeamFeb 06 2009Sep 20 2011MINOS is a long baseline neutrino oscillation experiment that uses two detectors separated by 734 km. The readout systems used for the two detectors are different and have to be independently calibrated. To verify and make a direct comparison of the calibrated ... More
Performance analysis for the new G-2 experimentJul 01 2016The new g-2 experiment at Fermilab aims to measure the muon anomalous magnetic moment by a fourfold improvement in precision compared to the BNL experiment. Achieving this goal requires the delivery of highly polarized 3.094 GeV/c muons with a narrow ... More
Towards commissioning the Fermilab Muon G-2 ExperimentFeb 16 2018Starting this summer, Fermilab will host a key experiment dedicated to the search for signals of new physics: The Fermilab Muon g-2 Experiment. Its aim is to precisely measure the anomalous magnetic moment of the muon. In full operation, in order to avoid ... More
Optical Structure and Proper-Motion Age of the Oxygen-rich Supernova Remnant 1E 0102-7219 in the Small Magellanic CloudJan 24 2006We present new optical emission-line images of the young SNR 1E 0102-7219 (E0102) in the SMC obtained with the HST Advanced Camera for Surveys (ACS). E0102 is a member of the oxygen-rich class of SNRs showing strong oxygen, neon , and other metal-line ... More
A new method of measuring electric dipole moments in storage ringsJul 02 2003Oct 12 2004A new highly sensitive method of looking for electric dipole moments of charged particles in storage rings is described. The major systematic errors inherent in the method are addressed and ways to minimize them are suggested. It seems possible to measure ... More
Highly enriched $^{28}$Si reveals remarkable optical linewidths and fine structure for well-known damage centersJul 27 2018Luminescence and optical absorption due to radiation damage centers in silicon has been studied exhaustively for decades, but is receiving new interest for applications as emitters for integrated silicon photonic technologies. While a variety of other ... More
Distance and intersection number in the curve graph of a surfaceSep 19 2018Mar 09 2019In this work, we study the cellular decomposition of $S$ induced by a filling pair of curves $v$ and $w$, $Dec_{v,w}(S) = S - (v \cup w)$, and its connection to the distance function $d(v,w)$ in the curve graph of a closed orientable surface $S$ of genus ... More
Nodal quasiparticle dynamics in the heavy fermion superconductor CeCoIn5 revealed by precision microwave spectroscopyOct 20 2012Sep 22 2013CeCoIn5 is a heavy fermion superconductor with strong similarities to the high-Tc cuprates, including quasi-two-dimensionality, proximity to antiferromagnetism, and probable d-wave pairing arising from a non-Fermi-liquid normal state. Experiments allowing ... More
Ejecta, Dust, and Synchrotron Radiation in B0540-69.3: A More Crab-Like Remnant than the CrabJul 25 2008We present near and mid-infrared observations of the pulsar-wind nebula (PWN) B0540-69.3 and its associated supernova remnant made with the {\it Spitzer Space Telescope}. We report detections of the PWN with all four IRAC bands, the 24 $\mu$m band of ... More
Characterization of the Si:Se+ spin-photon interfaceSep 26 2018Silicon is the most developed electronic and photonic technological platform and hosts some of the highest-performance spin and photonic qubits developed to date. A hybrid quantum technology harnessing an efficient spin-photon interface in silicon would ... More
The Cosmic Origins SpectrographSep 30 2011The Cosmic Origins Spectrograph (COS) is a moderate-resolution spectrograph with unprecedented sensitivity that was installed into the Hubble Space Telescope (HST) in May 2009, during HST Servicing Mission 4 (STS-125). We present the design philosophy ... More
The Role of Schema Matching in Large EnterprisesSep 09 2009To date, the principal use case for schema matching research has been as a precursor for code generation, i.e., constructing mappings between schema elements with the end goal of data transfer. In this paper, we argue that schema matching plays valuable ... More
Interlacement and Activities in Delta-MatroidsOct 28 2017We generalize theories of graph, matroid, and ribbon-graph activities to delta-matroids. As a result, we obtain an activities based feasible-set expansion for a transition polynomial of delta-matroids defined by Brijder and Hoogeboom. This result yields ... More
Combinatorics of the K-theory of affine GrassmanniansJul 01 2009We introduce a family of tableaux that simultaneously generalizes the tableaux used to characterize Grothendieck polynomials and k-Schur functions. We prove that the polynomials drawn from these tableaux are the affine Grothendieck polynomials and k-K-Schur ... More
Measuring the impact of input data on energy consumption of softwareNov 10 2014The amount of energy consumed during the execution of software, and the ability to predict future consumption, is an important factor in the design of embedded electronic systems. In this technical report I examine factors in the execution of software ... More
Particle relabelling symmetries and Noether's theorem for vertical slice modelsAug 15 2018We consider the variational formulation for vertical slice models introduced in Cotter and Holm (Proc Roy Soc, 2013). These models have a Kelvin circulation theorem that holds on all materially-transported closed loops, not just those loops on isosurfaces ... More
The Interlace PolynomialJan 12 2016In this paper, we survey results regarding the interlace polynomial of a graph, connections to such graph polynomials as the Martin and Tutte polynomials, and generalizations to the realms of isotropic systems and delta-matroids.
Neural Population Coding is Optimized by Discrete Tuning CurvesSep 09 2008Sep 24 2009The sigmoidal tuning curve that maximizes the mutual information for a Poisson neuron, or population of Poisson neurons, is obtained. The optimal tuning curve is found to have a discrete structure that results in a quantization of the input signal. The ... More
Observation of mutually enhanced collectivity in self-conjugate $^{76}_{38}$Sr$_{38}$Apr 10 2012The lifetimes of the first 2$^{+}$ states in the neutron-deficient $^{76,78}$Sr isotopes were measured using a unique combination of the $\gamma$-ray line-shape method and two-step nucleon exchange reactions at intermediate energies. The transition rates ... More
Cluster--Galaxy Interactions in ComaJan 22 2003The galaxies NGC 4911 and 4921 in the Coma cluster provide spectacular examples of luminous, grand design spirals passing through the hot intracluster medium of a rich cluster of galaxies. Chandra ACIS-I imaging of their environment, coupled with CFHT, ... More
Search for periodic gravitational radiation with the ALLEGRO gravitational wave detectorJul 11 2000We describe the search for a continuous signal of gravitational radiation from a rotating neutron star in the data taken by the ALLEGRO gravitational wave detector in early 1994. Since ALLEGRO is sensitive at frequencies near 1 kHz, only neutron stars ... More
Minisuperspace Examples of Quantization Using Canonical Variables of the Ashtekar Type: Structure and SolutionsOct 17 1995The Ashtekar variables have been use to find a number of exact solutions in quantum gravity and quantum cosmology. We investigate the origin of these solutions in the context of a number of canonical transformations (both complex and real) of the basic ... More
Why sauropods had long necks; and why giraffes have short necksSep 24 2012The necks of the sauropod dinosaurs reached 15 m in length: six times longer than that of the world record giraffe and five times longer than those of all other terrestrial animals. Several anatomical features enabled this extreme elongation, including: ... More
On the stabilization of ion sputtered surfacesJun 18 2007The classical theory of ion beam sputtering predicts the instability of a flat surface to uniform ion irradiation at any incidence angle. We relax the assumption of the classical theory that the average surface erosion rate is determined by a Gaussian ... More
Algebra and valuations related to the Tutte polynomialNov 23 2017This is a chapter destined for the book "Handbook of the Tutte Polynomial". The chapter is a composite. The first part is a brief introduction to Orlik-Solomon algebras. The second part sketches the theory of evaluative functions on matroid base polytopes ... More
A simple random matrix model for the vibrational spectrum of jammed packingsApr 11 2018Apr 27 2018To better understand the surprising low-frequency vibrational modes in structural glasses, we study the spectra of a large ensemble of sparse random matrices where disorder is controlled by the distribution of bond weights and network coordination. We ... More
The Principal Axis of the Virgo ClusterAug 30 2000Using accurate distances to individual Virgo cluster galaxies obtained by the method of Surface Brightness Fluctuations, we show that Virgo's brightest ellipticals have a remarkably collinear arrangement in three dimensions. This axis, which is inclined ... More
Probability Models for Degree Distributions of Protein Interaction NetworksJul 03 2005The degree distribution of many biological and technological networks has been described as a power-law distribution. While the degree distribution does not capture all aspects of a network, it has often been suggested that its functional form contains ... More
Numerical Method for Shock Front Hugoniot StatesSep 01 2005Jan 26 2006We describe a Continuous Hugoniot Method for the efficient simulation of shock wave fronts. This approach achieves significantly improved efficiency when the generation of a tightly spaced collection of individual steady-state shock front states is desired, ... More
CI Cam: A Shell-shocked X-ray NovaJul 13 2004We present radio imaging observations of the 1998 outburst of the peculiar emission line star CI Cam, taken about 1, 4, 75, 82, 93, 163, and 306 days after the beginning of the 31.64 March 1998 X-ray flare. The first two epochs show a resolved but compact ... More
Observable effects of anisotropic bubble nucleationMar 02 2010Jun 02 2010Our universe may have formed via bubble nucleation in an eternally-inflating background. Furthermore, the background may have a compact dimension--the modulus of which tunnels out of a metastable minimum during bubble nucleation--which subsequently grows ... More
Recursive Procedures for Krall-Sheffer OperatorsNov 13 2012Jun 30 2013We consider the Krall-Sheffer class of admissible, partial differential operators in the plane. We concentrate on algebraic structures, such as the role of commuting operators and symmetries. For the polynomial eigenfunctions, we give explicit forms of ... More
Phase transitions on the surface of a carbon nanotubeSep 03 2009A suspended carbon nanotube can act as a nanoscale resonator with remarkable electromechanical properties and the ability to detect adsorption on its surface at the level of single atoms. Understanding adsorption on nanotubes and other graphitic materials ... More
Kinematics of X-ray Emitting Components in Cassiopeia AJun 01 2004We present high-resolution X-ray proper motion measurements of Cassiopeia A using Chandra observations from 2000 and 2002. We separate the emission into four spectrally distinct classes: Si-dominated, Fe-dominated, low-energy-enhanced, and continuum-dominated. ... More
Deconstructing HD 28867Dec 31 2002The 3" pair of B9 stars, HD 28867, is one of the brightest X-ray sources in the Taurus-Auriga star forming region. In this multi-wavelength study, we attempt to deduce the source of the X-ray emission. We show that the East component is the X-ray source. ... More
IceRay: An IceCube-centered Radio-Cherenkov GZK Neutrino DetectorApr 08 2009We discuss design considerations and simulation results for IceRay, a proposed large-scale ultra-high energy (UHE) neutrino detector at the South Pole. The array is designed to detect the coherent Askaryan radio emission from UHE neutrino interactions ... More
Spin Motion in Electron Transmission through Ultrathin Ferromagnetic Films Accessed by Photoelectron SpectroscopyNov 08 2002Ab initio and model calculations demonstrate that the spin motion of electrons transmitted through ferromagnetic films can be analyzed in detail by means of angle- and spin-resolved core-level photoelectron spectroscopy. The spin motion appears as precession ... More
Very Long Baseline Neutrino Oscillation Experiment for Precise Measurements of Mixing Parameters and CP Violating EffectsMar 10 2003May 16 2003We analyze the prospects of a feasible, Brookhaven National Laboratory based, very long baseline (BVLB) neutrino oscillation experiment consisting of a conventional horn produced low energy wide band beam and a detector of 500 kT fiducial mass with modest ... More
Report on the Depth Requirements for a Massive Detector at HomestakeJul 23 2009Aug 09 2009This report provides the technical justification for locating a large detector underground in a US based Deep Underground Science and Engineering Laboratory. A large detector with a fiducial mass in the mega-ton scale will most likely be a multipurpose ... More
Combinatorial expansions in K-theoretic basesJun 08 2011We study the class $\mathcal C$ of symmetric functions whose coefficients in the Schur basis can be described by generating functions for sets of tableaux with fixed shape. Included in this class are the Hall-Littlewood polynomials, $k$-atoms, and Stanley ... More
Understanding complex magnetic order in disordered cobalt hydroxides through analysis of the local structureOct 01 2010Jan 10 2011In many ostensibly crystalline materials, unit-cell-based descriptions do not always capture the complete physics of the system due to disruption in long-range order. In the series of cobalt hydroxides studied here, Co(OH)$_{2-x}$(Cl)$_x$(H$_2$O)$_{n}$, ... More
Diagrammatic analysis of correlations in polymer fluids: Cluster diagrams via Edwards' field theoryFeb 20 2006A straightforward expansion of Edwards' functional integral representation of the grand partition function for a polymer liquid as an infinite set of Feynman diagrams is shown to yield a cluster expansion that is closely related to the corresponding Mayer ... More
A k-tableau characterization of k-Schur functionsMay 24 2005We study k-Schur functions characterized by k-tableaux, proving combinatorial properties such as a k-Pieri rule and a k-conjugation. This new approach relies on developing the theory of k-tableaux, and includes the introduction of a weight-permuting involution ... More
Colorful combinatorics and Macdonald polynomialsOct 02 2017The non-negative integer cocharge statistic on words was introduced in the 1970's by Lascoux and Sch\"utzenberger to combinatorially characterize the Hall-Littlewood polynomials. Cocharge has since been used to explain phenomena ranging from the graded ... More
A combinatorial formula for fusion coefficientJul 03 2012Using the expansion of the inverse of the Kostka matrix in terms of tabloids as presented by Egecioglu and Remmel, we show that the fusion coefficients can be expressed as an alternating sum over cylindric tableaux. Cylindric tableaux are skew tableaux ... More
Crystal approach to affine Schubert calculusAug 01 2014Jun 05 2015We apply crystal theory to affine Schubert calculus, Gromov-Witten invariants for the complete flag manifold, and the positroid stratification of the positive Grassmannian. We introduce operators on decompositions of elements in the type-$A$ affine Weyl ... More
Is the Difference Between the Pion Form Factor Measured in e+e- Annihilations and tau- Decays Due to an H- Propagator?Oct 04 2004We discuss how a charged Higgs propagator would modify the form factor in tau- -> pi- pi0 nu_tau decays.
The Role of PMESII Modeling in a Continuous Cycle of Anticipation and ActionJul 21 2016The inevitable incompleteness of any collection of PMESII models, along with poorly understood methods for combining heterogeneous models, leads to major uncertainty regarding the reliability of computational tools. This uncertainty is further exacerbated ... More
Topological Phases of the Heterotic StringMar 01 1992We analyze the phase structure of topological Calabi--Yau manifolds defined on the moduli space of instantons. We show in this framework that topological vacua describe new phases of the Heterotic String theory in which the flat directions corresponding ... More
Trace Diagrams, Matrix Minors, and Determinant IdentitiesMar 07 2009Dec 19 2009Trace diagrams are structured graphs with edges labeled by matrices. Each diagram has an interpretation as a particular multilinear function. We provide a rigorous combinatorial definition of these diagrams using a notion of signed graph coloring, and ... More
Order ideals in weak subposets of Young's lattice and associated unimodality conjecturesMay 07 2004The k-Young lattice Y^k is a weak subposet of the Young lattice containing partitions whose first part is bounded by an integer k>0. The Y^k poset was introduced in connection with generalized Schur functions and later shown to be isomorphic to the weak ... More
A Million-Second Chandra View of Cassiopeia ASep 30 2004We introduce a million-second observation of the supernova remnant Cassiopeia A with the Chandra X-ray Observatory. The bipolar structure of the Si-rich ejecta (NE jet and SW counterpart) is clearly evident in the new images, and their chemical similarity ... More
Sensitive Search for a Permanent Muon Electric Dipole MomentDec 07 2000We are proposing a new method to carry out a dedicated search for a permanent electric dipole moment (EDM) of the muon with a sensitivity at a level of 10^{-24} e cm. The experimental design exploits the strong motional electric field sensed by relativistic ... More
A first-principles study of the electronic structure of Iron-Selenium; Implications for electron-phonon superconductivityNov 22 2013Jan 08 2014We have performed density functional theory (DFT) calculations using the linearized augmented plane wave method (LAPW) with the local density approximation (LDA) functional to study the electronic structure of the iron-based superconductor Iron-Selenium ... More
The radial distributions of a heavy-light meson on a latticeSep 10 2002In an earlier work, the charge (vector) and matter (scalar) radial distributions of heavy-light mesons were measured in the quenched approximation on a 16^3 times 24 lattice with a quark-gluon coupling of 5.7, a lattice spacing of 0.17 fm, and a hopping ... More
SDSS J141624.08+134826.7: A Nearby Blue L Dwarf From the Sloan Digital Sky SurveyDec 18 2009We present the discovery of a bright (J = 13.1 mag) nearby L6 dwarf found in a search for L-type ultracool subdwarfs in the Sloan Digital Sky Survey (SDSS) Data Release 7. SDSS J141624.08+134826.7 exhibits blue near-infrared colors compared to other optically-typed ... More
Extending Continuum Models for Atom Probe SimulationFeb 27 2018This work describes extensions to existing level-set algorithms developed for application within the field of Atom Probe Tomography (APT). We present a new simulation tool for the simulation of 3D tomographic volumes, using advanced level set methods. ... More
Analysis of cosmic microwave background data on an incomplete skyAug 04 2000Nov 06 2001Measurement of the angular power spectrum of the cosmic microwave background is most often based on a spherical harmonic analysis of the observed temperature anisotropies. Even if all-sky maps are obtained, however, it is likely that the region around ... More
Deep Neural Network Compression for Aircraft Collision Avoidance SystemsOct 09 2018One approach to designing decision making logic for an aircraft collision avoidance system frames the problem as a Markov decision process and optimizes the system using dynamic programming. The resulting collision avoidance strategy can be represented ... More
Dynamical Behaviour of Fine Granular Glass/Bronze Mixtures under Vertical VibrationNov 05 2001We report the behaviour of mixtures of fine bronze and glass spheres under sinusoidal vertical vibration. Depending upon the ratio of their diameters and the amplitude and frequency of the vibration, we observe the formation of sharp separation boundaries ... More
Summing the Instanton Series in N=2 Superconformal Large-N QCDMay 27 1999We consider the multi-instanton collective coordinate integration measure in N=2 supersymmetric SU(N) gauge theory with N_F fundamental hypermultiplets. In the large-N limit, at the superconformal point where N_F=2N and all VEVs are turned off, the k-instanton ... More
The measurement, fitting and interpretation of the radial distributions of Heavy-Light mesons calculated on a lattice with dynamical fermionsDec 11 2002In our earlier work, the charge and matter radial distributions of heavy-light mesons were measured on a 16^3 times 24 lattice with a lattice spacing of a = 0.17 fm and a light quark mass about that of the strange quark. Several major improvements have ... More
Dynamical Mass of the M8+M8 Binary 2MASS J22062280-2047058ABSep 25 2009We present Keck laser guide star adaptive optics imaging of the M8+M8 binary 2MASS J2206-2047AB. Together with archival HST, Gemini-North, and VLT data, our observations span 8.3 years of the binary's 35 year orbital period, and we determine a total dynamical ... More
Asymptotic Linear Programming Lower Bounds for the Energy of Minimizing Riesz and Gauss ConfigurationsApr 14 2018Utilizing frameworks developed by Delsarte, Yudin and Levenshtein, we deduce linear programming lower bounds (as $N\to \infty$) for the Riesz energy of $N$-point configurations on the $d$-dimensional unit sphere in the so-called hypersingular case; i.e, ... More
Neutrino mixing and mass hierarchy in Gaussian landscapesOct 14 2008The flavor structure of the Standard Model may arise from random selection on a landscape. In a class of simple models, called "Gaussian landscapes," Yukawa couplings derive from overlap integrals of Gaussian zero-mode wavefunctions on an extra-dimensional ... More
The sigma orientation is an H-infinity mapApr 03 2002Jan 30 2004In "Elliptic spectra, the Witten genus, and the Theorem of the cube" (Invent. Math. 146 (2001)), the authors constructed a natural map from the Thom spectrum MU<6> to any elliptic spectrum, called the "sigma orientation". MU<6> is an H-infinity ring spectrum, ... More
Compact Binary Waveform Center-of-Mass CorrectionsApr 09 2019May 01 2019We present a detailed study of the center-of-mass (COM) motion seen in simulations produced by the Simulating eXtreme Spacetimes (SXS) collaboration. We investigate potential physical sources for the large COM motion in binary black hole (BBH) simulations ... More
Using simulation studies to evaluate statistical methodsDec 08 2017Dec 05 2018Simulation studies are computer experiments that involve creating data by pseudorandom sampling. The key strength of simulation studies is the ability to understand the behaviour of statistical methods because some 'truth' (usually some parameter/s of ... More
A Comparison of Popular Point Configurations on $\mathbb{S}^2$Jul 13 2016Aug 23 2016There are many ways to generate a set of nodes on the sphere for use in a variety of problems in numerical analysis. We present a survey of quickly generated point sets on $\mathbb{S}^2$, examine their equidistribution properties, separation, covering, ... More
Femtosecond wavepacket interferometry using the rotational dynamics of a trapped cold molecular ionNov 14 2014A Ramsey-type interferometer is suggested, employing a cold trapped ion and two time-delayed off-resonant femtosecond laser pulses. The laser light couples to the molecular polarization anisotropy, inducing rotational wavepacket dynamics. An interferogram ... More
A Study of Degenerate Four-quark states in SU(2) Lattice Monte CarloAug 02 1995Aug 08 1995The energies of four-quark states are calculated for geometries in which the quarks are situated on the corners of a series of tetrahedra and also for geometries that correspond to gradually distorting these tetrahedra into a plane. The interest in tetrahedra ... More
Compact Binary Waveform Center-of-Mass CorrectionsApr 09 2019We present a detailed study of the center-of-mass (COM) motion seen in simulations produced by the Simulating eXtreme Spacetimes (SXS) collaboration. We investigate potential physical sources for the large COM motion in binary black hole (BBH) simulations ... More
The Automated Mapping of Plans for Plan RecognitionFeb 27 2013To coordinate with other agents in its environment, an agent needs models of what the other agents are trying to do. When communication is impossible or expensive, this information must be acquired indirectly via plan recognition. Typical approaches to ... More
Unravelling quantum carpets: a travelling wave approachJun 28 1999Aug 08 1999Quantum carpets are generic spacetime patterns formed in the probability distributions P(x,t) of one-dimensional quantum particles, first discovered in 1995. For the case of an infinite square well potential, these patterns are shown to have a detailed ... More
Computing the Ramsey Number $R(K_5-P_3,K_5)$Mar 29 2012We give a computer-assisted proof of the fact that $R(K_5-P_3, K_5)=25$. This solves one of the three remaining open cases in Hendry's table, which listed the Ramsey numbers for pairs of graphs on 5 vertices. We find that there exist no $(K_5-P_3,K_5)$-good ... More
Statistical Understanding of Quark and Lepton Masses in Gaussian LandscapesJul 24 2007Aug 10 2007The fundamental theory of nature may allow a large landscape of vacua. Even if the theory contains a unified gauge symmetry, the 22 flavor parameters of the Standard Model, including neutrino masses, may be largely determined by the statistics of this ... More
Inferring nonlinear parabolic field equations from modulus dataNov 26 2004We give a means for measuring the equation of evolution of a complex scalar field that is known to obey an otherwise unspecified (2+1)-dimensional dissipative nonlinear parabolic differential equation, given field moduli over three closely-spaced planes. ... More
Electromagnetic interaction between a metallic nanoparticle and surface in tunnelling proximity modelling and experimentJul 01 2009We simulate the localized surface plasmon resonances of an Au nanoparticle within tunneling proximity of a Au substrate and demonstrate that the modes may be identified with those responsible for light emission from a scanning tunneling microscope. Relative ... More
Enhancing Sparsity by Reweighted L1 MinimizationNov 10 2007It is now well understood that (1) it is possible to reconstruct sparse signals exactly from what appear to be highly incomplete sets of linear measurements and (2) that this can be done by constrained L1 minimization. In this paper, we study a novel ... More
A Comparison of Popular Point Configurations on $\mathbb{S}^2$Jul 13 2016Oct 24 2016There are many ways to generate a set of nodes on the sphere for use in a variety of problems in numerical analysis. We present a survey of quickly generated point sets on $\mathbb{S}^2$, examine their equidistribution properties, separation, covering, ... More