Results for "Michael Harris"

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Incorrigible RepresentationsNov 12 2018Dec 25 2018As a consequence of his numerical local Langlands correspondence for $GL(n)$, Henniart deduced the following theorem: If $F$ is a nonarchimedean local field and if $\pi$ is an irreducible admissible representation of $GL(n,F)$, then, after a finite sequence ... More
Dimer Statistics on a Bethe LatticeAug 27 2004We discuss the exact solutions of various models of the statistics of dimer coverings of a Bethe lattice. We reproduce the well-known exact results for noninteracting hard-core dimers by both a very simple geometrical argument and a general algebraic ... More
Large deviation analysis of a simple information engineJun 26 2015Information thermodynamics provides a framework for studying the effect of feedback loops on entropy production. It has enabled the understanding of novel thermodynamic systems such as the information engine which can be seen as a modern version of `Maxwell's ... More
Constraining CP-violating Higgs Sectors at the LHC using gluon fusionJun 12 2014We investigate the constraints that the LHC can set on a 126 GeV Higgs boson that is an admixture of CP eigenstates. Traditional analyses rely on Higgs couplings to massive vector bosons, which are suppressed for CP-odd couplings, so that these analyses ... More
The local Langlands conjecture for GL(n) over a p-adic field, n < pNov 29 1996Let F be a p-adic field and n a positive integer. The local Langlands conjecture asserts the existence of a bijection between irreducible admissible representations of GL(n,F) and n-dimensional admissible representations of the Weil-Deligne group of F. ... More
On the local Langlands correspondenceApr 22 2003The local Langlands correspondence for GL(n) of a non-Archimedean local field $F$ parametrizes irreducible admissible representations of $GL(n,F)$ in terms of representations of the Weil-Deligne group $WD_F$ of $F$. The correspondence, whose existence ... More
Testing rationality of coherent cohomology of Shimura varietiesDec 09 2012Let $G' \subset G$ be an inclusion of reductive groups whose real points have a non-trivial discrete series. Combining ergodic methods of Burger-Sarnak and the author with a positivity argument due to Li and the classification of minimal $K$-types of ... More
Torsion groups of elliptic curves over the $\mathbb Z_p$-extensions of $\mathbb Q$Aug 15 2018Oct 08 2018We determine, for an elliptic curve $E/\mathbb Q$ and for all $p$, all the possible torsion groups $E(\mathbb Q_{\infty, p})_{tors}$, where $\mathbb Q_{\infty, p}$ is the $\mathbb Z_p$-extension of $\mathbb Q$.
Weight zero Eisenstein cohomology of Shimura varieties via Berkovich spacesAug 08 2012This brief article gives an alternative interpretation, based on a theorem of Berkovich, of the Eisenstein classes in the cohomology of Shimura varieties, used in forthcoming work of the author with K. W. Lan, R. Taylor, and J. Thorne.
Theoretical Foundation of the Weighted Laplace Inpainting ProblemJan 27 2018Laplace interpolation is a popular approach in image inpainting using partial differential equations. The classic approach considers the Laplace equation with mixed boundary conditions. Recently a more general formulation has been proposed where the differential ... More
Limits from CGRO/EGRET Data on the Use of Antimatter as a Power Source by Extraterrestrial CivilizationsDec 20 2001Jun 15 2002I argue that the existence of cold antimatter in bulk is not permitted by the Standard Model, so that if a gamma-ray signature from antiproton annihilation were to be detected, it must represent either new physics or the action of intelligence. Time variability ... More
p-adic measures and square roots of triple product L-functionsOct 23 1996Let p be a prime number, and let f, g, and h be three modular forms of weights $\kappa$, $\lambda$, and $\mu$ for $SL(2,\Bbb{Z})$. We suppose $\kappa \geq \lambda + \mu$. In joint work with Kudla, one of the authors obtained a formula for the normalized ... More
Period relations and special values of Rankin-Selberg $L$-functionsAug 26 2016This is a survey of recent work on values of Rankin-Selberg $L$-functions of pairs of cohomological automorphic representations that are {\it critical} in Deligne's sense. The base field is assumed to be a CM field. Deligne's conjecture is stated in the ... More
Period relations and special values of Rankin-Selberg $L$-functionsAug 26 2016Dec 18 2016This is a survey of recent work on values of Rankin-Selberg $L$-functions of pairs of cohomological automorphic representations that are {\it critical} in Deligne's sense. The base field is assumed to be a CM field. Deligne's conjecture is stated in the ... More
Whittaker periods, motivic periods, and special values of tensor product L-functionsAug 23 2013Aug 28 2014Let $\mathcal K$ be an imaginary quadratic field. Let $\Pi$ and $\Pi'$ be irreducible generic cohomological automorphic representation of $GL(n)/{\mathcal K}$ and $GL(n-1)/{\mathcal K}$, respectively. Each of them can be given two natural rational structures ... More
Thermal inertia of near-Earth asteroids and implications for the magnitude of the Yarkovsky effectApr 15 2007Thermal inertia determines the temperature distribution over the surface of an asteroid and therefore governs the magnitude the Yarkovsky effect. The latter causes gradual drifting of the orbits of km-sized asteroids and plays an important role in the ... More
NEOSurvey 1: Initial results from the Warm Spitzer Exploration Science Survey of Near Earth Object PropertiesAug 12 2016Near Earth Objects (NEOs) are small Solar System bodies whose orbits bring them close to the Earth's orbit. We are carrying out a Warm Spitzer Cycle 11 Exploration Science program entitled NEOSurvey --- a fast and efficient flux-limited survey of 597 ... More
Dark Matter Halos in Galaxies and Globular Cluster Populations. II: Metallicity and MorphologyApr 13 2015An increasing body of data reveals a one-to-one linear correlation between galaxy halo mass and the total mass in its globular cluster (GC) population, M_{GCS} ~ M_h^{1.03 \pm 0.03}, valid over 5 orders of magnitude. We explore the nature of this correlation ... More
Upper semicontinuity of the lamination hullSep 30 2016Let $K \subseteq \mathbb{R}^{2 \times 2}$ be a compact set, let $K^{rc}$ be its rank-one convex hull, and let $L(K)$ be its lamination convex hull. It is shown that the mapping $K \to \overline{L(K)}$ is not upper semicontinuous on the diagonal matrices ... More
Heat Kernels and CyclesMay 26 2005We use the heat kernel (on differential forms) on a compact Riemannian manifold to assign a real number to a k-tuple of cycles on the manifold satisfying certain conditions. If k is 2, this number is the ordinary topological linking number, an integer ... More
Self-field and magnetic-flux quantum mechanicsApr 06 2005Self-field and quantized magnetic-flux are employed to generate the quantum numbers n, m, and l of atomic physics. Wave-particle duality is shown to be a natural outcome of having a particle and its self-field.
Optimal angle of the holomorphic functional calculus for the classical Ornstein-Uhlenbeck operator on $L^p$Dec 20 2018We give a simple proof of the fact that the classical Ornstein-Uhlenbeck operator $L$ is R-sectorial of angle $arcsin|1-2/p|$ on $L^{p}(\mathbb{R}^{n},\exp(-|x|^2/2)dx)$ (for $1<p<\infty$). Applying the abstract holomorphic functional calculus theory ... More
Detecting inclusions with a generalized impedance condition from electrostatic data via samplingAug 10 2017Oct 15 2018In this paper, we derive a Sampling Method to solve the inverse shape problem of recovering an inclusion with a generalized impedance condition from electrostatic Cauchy data. The generalized impedance condition is a second-order differential operator ... More
On a conjecture of JacquetNov 21 2001In this note, we prove in full generality a conjecture of Jacquet concerning the nonvanishing of the triple product L-function at the central point. Let $\kay$ be a number field and let $\pi_i$, $i=1$, 2, 3 be cuspidal automorphic representations of $GL_2(\A)$ ... More
Categoricity and covering spacesDec 10 2014This thesis develops some of the basic model theory of covers of algebraic curves. In particular, an equivalence between the good model-theoretic behaviour of the modular j-function, and the openness of certain Galois representations in the Tate-modules ... More
A short proof of the thumbtack lemmaApr 17 2013We give a short proof of the main algebraic result of \cite{zilber2006covers}, also known as the `thumbtack lemma'.
Dark Matter Halos in Galaxies and Globular Cluster PopulationsApr 07 2014We combine a new, comprehensive database for globular cluster populations in all types of galaxies with a new calibration of galaxy halo masses based entirely on weak lensing. Correlating these two sets of data, we find that the mass ratio $\eta \equiv ... More
Variations in Star Formation History and the Red Giant Branch TipJan 20 2004We examine the reliability of the tip of the red giant branch (TRGB) as a distance indicator for stellar populations with different star formation histories (SFHs) when photometric errors and completeness corrections at the TRGB are small. In general, ... More
On the Spectral Evolution of Cool, Helium-Atmosphere White Dwarfs: Detailed Spectroscopic and Photometric Analysis of DZ StarsMar 29 2007We present a detailed analysis of a large spectroscopic and photometric sample of DZ white dwarfs based on our latest model atmosphere calculations. We revise the atmospheric parameters of the trigonometric parallax sample of Bergeron, Leggett, & Ruiz ... More
Whittaker rational structures and special values of the Asai $L$-functionAug 08 2014Nov 27 2014Let $F$ be a totally real number field and $E/F$ a totally imaginary quadratic extension of $F$. Let $\Pi$ be a cohomological, conjugate self-dual cuspidal automorphic representation of $GL_n(\mathbb A_E)$. Under a certain non-vanishing condition we relate ... More
Deligne's conjecture for automorphic motives over CM-fields, Part I: factorizationFeb 08 2018This is the first of two papers devoted to the relations between Deligne's conjecture on critical values of motivic $L$-functions and the multiplicative relations between periods of arithmetically normalized automorphic forms on unitary groups. The present ... More
A game-theoretic framework for classifier ensembles using weighted majority voting with local accuracy estimatesFeb 03 2013In this paper, a novel approach for the optimal combination of binary classifiers is proposed. The classifier combination problem is approached from a Game Theory perspective. The proposed framework of adapted weighted majority rules (WMR) is tested against ... More
Astrophysical Effects of nu+gamma-->nu+gamma+gamma and Its Crossed ProcessesJul 09 1997Recently, Dicus and Repko computed nu gamma --> nu gamma gamma for energies below the threshold for e^{+}e^{-} pair production. They found across section on the order of 10^{-52} omega ^{gamma} with gamma =10, where omega is the CMS energy of one of the ... More
interAdapt -- An Interactive Tool for Designing and Evaluating Randomized Trials with Adaptive Enrollment CriteriaApr 02 2014Jun 18 2014The interAdapt R package is designed to be used by statisticians and clinical investigators to plan randomized trials. It can be used to determine if certain adaptive designs offer tangible benefits compared to standard designs, in the context of investigators' ... More
Consistency between ARPES and STM measurements on SmB$_6$Oct 31 2018Strongly correlated topological surface states are promising platforms for next-generation quantum applications, but they remain elusive in real materials. The correlated Kondo insulator SmB$_6$ is one of the most promising candidates, with theoretically ... More
Evolution of H$_2$O, CO, and CO$_2$ Production in Comet C/2009 P1 Garradd During the 2011-2012 ApparitionDec 23 2014We present analysis of high spectral resolution NIR spectra of CO and H$_2$O in comet C/2009 P1 (Garradd) taken during its 2011-2012 apparition with the CSHELL instrument on NASA's Infrared Telescope Facility (IRTF). We also present analysis of observations ... More
Deterministic parallel algorithms for fooling polylogarithmic juntas and the Lovasz Local LemmaOct 11 2016Many randomized algorithms can be derandomized efficiently using either the method of conditional expectations or probability spaces with low (almost-) independence. A series of papers, beginning with work by Luby (1988) and continuing with Berger & Rompel ... More
Near field imaging of small isotropic and extended anisotropic scatterersJan 12 2016Sep 11 2016In this paper, we consider two time-harmonic inverse scattering problems of reconstructing penetrable inhomogeneous obstacles from near field measurements. First we appeal to the Born approximation for reconstructing small isotropic scatterers via the ... More
Discovery Mass Reach for Excited Quarks at Hadron CollidersSep 11 1996If quarks are composite particles then excited states are expected. We estimate the discovery mass reach as a function of integrated luminosity for excited quarks decaying to dijets at the Tevatron, LHC, and a Very Large Hadron Collider (VLHC). At the ... More
UCD Candidates in the Hydra ClusterAug 10 2007NGC 3311, the giant cD galaxy in the Hydra cluster (A1060), has one of the largest globular cluster systems known. We describe new Gemini GMOS (g',i') photometry of the NGC 3311 field which reveals that the red, metal-rich side of its globular cluster ... More
Determination of step--edge barriers to interlayer transport from surface morphology during the initial stages of homoepitaxial growthMar 21 1995We use analytic formulae obtained from a simple model of crystal growth by molecular--beam epitaxy to determine step--edge barriers to interlayer transport. The method is based on information about the surface morphology at the onset of nucleation on ... More
Measure changes with extinctionNov 11 2008Dec 18 2008We consider a change of measure by a martingale $Z_t$ and clarify that in general $1/Z_t$ is only a supermartingale under the changed measure. We then give a necessary and sufficient condition for the event that the limit of the martingale is zero to ... More
Asymptotic convergence of spectral inverse iterations for stochastic eigenvalue problemsJun 12 2017We consider and analyze applying a spectral inverse iteration algorithm and its subspace iteration variant for computing eigenpairs of an elliptic operator with random coefficients. With these iterative algorithms the solution is sought from a finite ... More
Multiparametric shell eigenvalue problemsMar 10 2018Mar 16 2018The eigenproblem for thin shells of revolution under uncertainty in material parameters is discussed. Here the focus is on the smallest eigenpairs. Shells of revolution have natural eigenclusters due to symmetries, moreover, the eigenpairs depend on a ... More
Bipartite matrix-valued tensor product correlations that are not finitely representableJun 22 2018We consider the matrix-valued generalizations of bipartite tensor product quantum correlations and bipartite infinite-dimensional tensor product quantum correlations, respectively. These sets are denoted by $C_q^{(n)}(m,k)$ and $C_{qs}^{(n)}(m,k)$, respectively, ... More
On-off Threshold Models of Social ContagionSep 10 2012We study binary state contagion dynamics on a social network where nodes act in response to the average state of their neighborhood. We model the competing tendencies of imitation and non-conformity by incorporating an off-threshold into standard threshold ... More
Symmetry Analysis of Multiferroic Co_3TeO_6Feb 16 2012A phenomenological explanation of the magnetoelectric behavior of Co_3TeO_6 is developed. We explain the second harmonic generation data and the magnetic field induced spontaneous polarization in the magnetically ordered phase below 20K.
Universality of the Future Chronological BoundaryApr 04 1997Sep 26 1997The purpose of this note is to establish, in a categorical manner, the universality of the Geroch-Kronheimer-Penrose causal boundary when considering the types of causal structures that may profitably be put on any sort of boundary for a spacetime. Actually, ... More
Electromagnetically Induced Transparency and Quantum Heat EnginesNov 03 2016We describe how electromagnetically induced transparency may be used to construct a non-traditional near-ideal quantum heat engine as constrained by the Second Law. The engine is pumped by a thermal reservoir that may be either hotter or colder than that ... More
Branching Brownian motion: Almost sure growth along unscaled pathsNov 11 2008We give new results on the growth of the number of particles in a dyadic branching Brownian motion which follow within a fixed distance of a path $f:[0,\infty)\to \mathbb{R}$. We show that it is possible to count the number of particles without rescaling ... More
Nonlocal Modulation of Entangled PhotonsAug 06 2008We consider ramifications of the use of high speed light modulators to questions of correlation and measurement of time-energy entangled photons. Using phase modulators, we find that temporal modulation of one photon of an entangled pair, as measured ... More
Topology of the Future Chronological Boundary: Universality for Spacelike BoundariesJul 19 1999Nov 10 1999A method is presented for imputing a topology for any chronological set, i.e., a set with a chronology relation, such as a spacetime or a spacetime with some sort of boundary. This topology is shown to have several good properties, such as replicating ... More
Error-prone polymerase activity causes multinucleotide mutations in humansDec 05 2013Apr 29 2014About 2% of human genetic polymorphisms have been hypothesized to arise via multinucleotide mutations (MNMs), complex events that generate SNPs at multiple sites in a single generation. MNMs have the potential to accelerate the pace at which single genes ... More
Constraints from $v_2$ fluctuations for the initial state geometry of heavy-ion collisionsJan 09 2014The ability to accurately compute the series of coefficients $v_n$ characterizing the momentum space anisotropies of particle production in ultrarelativistic heavy ion collisions as a function of centrality is widely regarded as a triumph of fluid dynamics ... More
Powers of Ideals and Fibers of MorphismsJul 26 2008Let X\subset PP^n be a projective scheme over a field, and let phi:X --> Y be a finite morphism. Our main result is a formula in terms of global data for the maximum of the Castelnuovo-Mumford regularity of the fibers of \phi, considered as subschemes ... More
Analysis of new direct sampling indicators for far-field measurementsJan 08 2019Feb 12 2019This article focuses on the analysis of three direct sampling indicators which can be used for recovering scatterers from the far-field pattern of time-harmonic acoustic measurements. These methods fall under the category of sampling methods where an ... More
An a.e. lower bound for Hausdorff dimension under vertical projections in the Heisenberg groupNov 30 2018Mar 10 2019An improved a.e. lower bound is given for Hausdorff dimension under vertical projections in the first Heisenberg group.
A new characterization of the exceptional Lie algebrasMar 13 2014For a simple Lie algebra, over $\mathbb{C}$, we consider the weight which is the sum of all simple roots and denote it $\tilde{\alpha}$. We formally use Kostant's weight multiplicity formula to compute the "dimension" of the zero-weight space. In type ... More
Categoricity of modular and Shimura curvesApr 17 2013Sep 14 2015We describe a model-theoretic setting for the study of Shimura varieties, and study the interaction between model theory and arithmetic geometry in this setting. In particular, we show that the model-theoretic statement of a certain $\mathcal{L}_{\omega_1, ... More
A direct method for reconstructing inclusions and boundary conditions from electrostatic dataApr 24 2017Feb 22 2018In this paper, we will discuss the use of a Sampling Method to reconstruct impenetrable inclusions from Electrostatic Cauchy data. We consider the case of a perfectly conducting and impedance inclusion. In either case, we show that the Dirichlet to Neumann ... More
The factorization method for a defective region in an anisotropic materialOct 14 2014In this paper we consider the inverse acoustic scattering (in \mathbb{R}^3) or electromagnetic scattering (in \mathbb{R}^2, for the scalar TE-polarization case) problem of reconstructing possibly multiple defective penetrable regions in a known anisotropic ... More
Near field imaging of small isotropic and extended anisotropic scatterersJan 12 2016Jan 17 2017In this paper, we consider two time-harmonic inverse scattering problems of reconstructing penetrable inhomogeneous obstacles from near field measurements. First we appeal to the Born approximation for reconstructing small isotropic scatterers via the ... More
The Binary White Dwarf LHS 3236Sep 04 2013The white dwarf LHS 3236 (WD1639+153) is shown to be a double-degenerate binary, with each component having a high mass. Astrometry at the U.S. Naval Observatory gives a parallax and distance of 30.86 +/- 0.25 pc and a tangential velocity of 98 km/s, ... More
Classifying Possible Tilting of Oxygen Octahedra in PerovskitesDec 23 2010The list of possible commensurate phases obtained from the parent tetragonal phase of perovskites by allowing the tilting of octahedra of oxygen ions is reexamined. It is found that many structures allowed by symmetry are not consistent with the constraint ... More
Landau Potential for Multiferroic Mn_2GeO_4Jan 18 2017A high-order Landau potential for Mn_2GeO_4 is developed.
Landau Theory of Tilting of Oxygen Octahedra in PerovskitesJun 13 2011The list of possible commensurate phases obtained from the parent tetragonal phase of Ruddlesden-Popper systems, A$_{n+1}$B$_n$C$_{3n+1}$ for general $n$ due to a single phase transition involving the reorienting of octahedra of C (oxygen) ions is reexamined ... More
Phonons and their Coupling to Magnons in n=2 Ruddlesden-Popper CompoundsNov 30 2010Jan 25 2011The number of absorption and Raman optical modes for each Wyckoff orbit in the high-temperature tetragonal (I4/mmm) parent lattice of the Ruddlesden-Popper compounds Ca$_3$X$_2$O$_7$, with X=Mn or X=Ti is given. We analyze the effect of sequential perturbations ... More
Possible Orientationally Ordered States of Bucky-CubaneFeb 13 2009For temperatures above $T^*=130$K C$_{60} \cdot$C$_8$H$_8$ forms a cubic crystal consisting of two interpenetrating fcc sublattices, one of freely rotating Buckys C$_{60}$ and the other of orientationally ordered cubane C$_8$H$_8$. The crystal structure ... More
Spectroscopy with Multichannel Correlation RadiometersApr 20 2005Correlation radiometers make true differential measurements in power with high accuracy and small systematic errors. This receiver architecture has been used in radio astronomy for measurements of continuum radiation for over 50 years; this article examines ... More
Effects of an impermeable wall in dissipative dynamics of saturated porous mediaFeb 27 2016A phase transition model for porous media in consolidation is studied. The model is able to describe the phenomenon of fluid-segregation during the consolidation process, i.e., the coexistence of two phases differing from fluid content inside the porous ... More
A lower bound for the a.e. behaviour of Hausdorff dimension under vertical projections in the Heisenberg groupNov 30 2018Dec 07 2018It is shown that for a Borel set $A$ in the Heisenberg group with $\dim A >2$, \[ \dim P_{\mathbb{V}^{\perp}_{\theta}} A \geq \begin{cases} \frac{\dim A}{2} &\text{ if } \dim A \in \left(2, \frac{5}{2} \right] \\ \frac{ \dim A(\dim A + 2)}{4\dim A -1} ... More
Improved decay of conical averages of the Fourier transformJun 21 2018Jan 18 2019An improved lower bound is given for the decay of conical averages of Fourier transforms of measures, in dimensions $d \geq 4$. The proof uses a weighted version of the broad restriction inequality, a narrow decoupling inequality for the cone, and some ... More
Refined Strichartz inequalities for the wave equationMay 18 2018Jun 08 2018Some analogues of the Schr\"odinger refined Strichartz inequalities (Du, Guth, Li and Zhang) are obtained for the wave equation. These are used to improve the best known $L^2$ fractal Strichartz inequalities for the wave equation in dimensions $d \geq ... More
Static- and Stationary-complete Spacetimes: Algebraic and Causal StructuresDec 24 2014Jun 05 2015This is intended as an analysis of the global properties of static and stationary spacetimes with complete (timelike) Killing field, with particular attention to quotients by group actions. This is presented in terms of algebraic structures which are ... More
Simultaneous Modelling of the Stellar Halo and Globular Cluster System of NGC 5128Nov 27 2002An important test for models of galaxy formation lies in the metallicity distribution functions (MDFs) of spheroid stars and their globular clusters (GCs).We have compared the MDFs obtained from spectroscopy of the GCs and the star-by-star photometry ... More
Computational Solutions for Today's NavyJan 10 2008Apr 08 2008New methods are being employed to meet the Navy's changing software-development environment.
SUSY Production Cross SectionsMar 03 1999We summarize the status of next-to-leading order perturbative quantum chromodynamics (pQCD) calculations of the cross sections for the production of squarks, gluinos, neutralinos, charginos, and sleptons as a function of the produced sparticle masses ... More
Closing up on Dark Sectors at Colliders: from 14 to 100 TeVSep 09 2015We investigate the reach of the LHC Run 2 and that of a future circular hadron collider with up to 100 TeV centre of mass energy for the exploration of potential Dark Matter sectors. These dark sectors are conveniently and broadly described by simplified ... More
p-adic L-functions for unitary groupsFeb 04 2016Aug 25 2016This paper completes the construction of $p$-adic $L$-functions for unitary groups. More precisely, in 2006, the last three named authors proposed an approach to constructing such $p$-adic $L$-functions (Part I). Building on more recent results, including ... More
On the Rigid Cohomology of Certain Shimura VarietiesNov 25 2014We construct the compatible system of $l$-adic representations associated to a regular algebraic cuspidal automorphic representation of $GL_n$ over a CM (or totally real) field and check local-global compatibility for the $l$-adic representation away ... More
\widehat{G}-local systems on smooth projective curves are potentially automorphicSep 12 2016Let $X$ be a smooth, projective, geometrically connected curve over a finite field $\mathbb{F}_q$, and let $G$ be a split semisimple algebraic group over $\mathbb{F}_q$. Its dual group $\widehat{G}$ is a split reductive group over $\mathbb{Z}$. Conjecturally, ... More
The VLA/ALMA Nascent Disk and Multiplicity (VANDAM) Survey of Perseus Protostars. VI. Characterizing the Formation Mechanism for Close Multiple SystemsSep 17 2018We present Atacama Large Millimeter/submillimeter Array (ALMA) observations of multiple protostar systems in the Perseus molecular cloud previously detected by the Karl G. Jansky Very Large Array (VLA). We observed 17 close ($<$600~AU separation) multiple ... More
An Investigation into the Spectral Properties of Bright Fermi BlazarsMay 12 2014We investigate the spectral properties of blazars detected with the Fermi-Large Area Telescope (LAT) in the high energy regime 100 MeV - 100 GeV. We find that over long timescales a log-parabola provides an adequate description of the spectrum in almost ... More
Identifying Breaks and Curvature in the Fermi Spectra of Bright FSRQs and Constraining the Emission RegionOct 02 2012Deviation of the gamma-ray energy spectra of Flat Spectrum Radio Quasars (FSRQs) from a simple power law has been previously observed but the cause of this remains unidentified. If the gamma-ray emission region is close to the central black hole then ... More
Spatial and Temporal Variability of the Gamma Radiation from Earth's Atmosphere during a Solar CycleAug 21 2003The Solar Maximum Mission satellite's Gamma Ray Spectrometer observed Earth's atmosphere for most of the period 1980-1989. Its 28deg orbit ensured that a range of geomagnetic latitudes (geomagnetic cutoff rigidities) was sampled. We measured the variation ... More
Machine Learning Uncertainties with Adversarial Neural NetworksJul 23 2018Jan 03 2019Machine Learning is a powerful tool to reveal and exploit correlations in a multi-dimensional parameter space. Making predictions from such correlations is a highly non-trivial task, in particular when the details of the underlying dynamics of a theoretical ... More
A Color-Magnitude Diagram for a Globular Cluster In the Giant Elliptical Galaxy NGC 5128Jun 30 1998The Hubble Space Telescope has been used to obtain WFPC2 (V,I) photometry for a large sample of stars in the outer halo of the giant elliptical NGC 5128 (d = 4 Mpc). The globular cluster N5128-C44, at the center of the Planetary Camera field, is well ... More
Exponential growth rates in a typed branching diffusionApr 03 2007We study the high temperature phase of a family of typed branching diffusions initially studied in [Ast\'{e}risque 236 (1996) 133--154] and [Lecture Notes in Math. 1729 (2000) 239--256 Springer, Berlin]. The primary aim is to establish some almost-sure ... More
Identifying Breaks and Curvature in the Fermi Spectra of Bright Flat Spectrum Radio QuasarsOct 22 2012Nov 13 2012Knowing the site of gamma-ray emission in AGN jets will do much for our understanding of the physics of the source. In particular, if the emission region is close to the black hole then absorption of gamma-rays with photons from the broad-line region ... More
Unitarity-controlled resonances after Higgs discoveryMar 25 2015Jul 16 2015If the recently discovered Higgs boson's couplings deviate from the Standard Model expectation, we may anticipate new resonant physics in the weak boson fusion channels resulting from high scale unitarity sum rules of longitudinal gauge boson scattering. ... More
Peer assessment enhances student learningOct 14 2014Feedback has a powerful influence on learning, but it is also expensive to provide. In large classes, it may even be impossible for instructors to provide individualized feedback. Peer assessment has received attention lately as a way of providing personalized ... More
Defect production in quench from current-carrying non-equilibrium stateAug 31 2015Mar 28 2016We consider the defect production of a quantum system, initially prepared in a current-carrying non-equilibrium state, during its unitary driving through a quantum critical point. At low values of the initial current, the quantum Kibble-Zurek scaling ... More
Discovering New Interactions at CollidersOct 16 1996We summarize results of the 1996 Snowmass workshop on future prospects for discovering dynamical electroweak symmetry breaking, compositeness, and anomalous couplings of quarks at colliders. We present the mass reach of the Tevatron to a color singlet ... More
Searches for Dijet Resonances at Hadron CollidersOct 24 2011We review the experimental searches for new particles in the dijet mass spectrum conducted at the CERN SppS, the Fermilab Tevatron Collider, and the CERN Large Hadron Collider. The theory of the QCD background and new particle signals is reviewed, with ... More
Spine proofs for Lp-convergence of branching-diffusion martingalesNov 02 2006Using the foundations laid down in Hardy and Harris (2006) ["A new formulation of the spine approach in branching diffusions", arXiv:math.PR/0611054], we present new spine proofs of the L^p-convergence p>=1) of some key `additive' martingales for three ... More
Conformal great circle flows on the three-sphereAug 29 2013May 05 2015We consider a closed orientable Riemannian 3-manifold $(M,g)$ and a vector field $X$ with unit norm whose integral curves are geodesics of $g$. Any such vector field determines naturally a 2-plane bundle contained in the kernel of the contact form of ... More
Thermal conductivity of diamond-loaded glues for the ATLAS particle physics detectorAug 04 2010Aug 16 2010The ATLAS experiment is one of two large general-purpose particle detectors at the Large Hadron Collider (LHC) at the CERN laboratory in Geneva, Switzerland. ATLAS has been collecting data from the collisions of protons since December 2009, in order to ... More
Charge and Spin Ordering in the Mixed Valence Compound LuFe2O4Mar 11 2010Landau theory and symmetry considerations lead us to propose an explanation for several seemingly paradoxical behaviors of charge ordering (CO) and spin ordering (SO) in the mixed valence compound LuFe2O4. Both SO and CO are highly frustrated. We analyze ... More
A new formulation of the spine approach to branching diffusionsNov 02 2006We present a formalization of the spine change of measure approach for branching diffusions that improves on the scheme laid out for branching Brownian motion in Kyprianou (2004) ["Travelling wave solutions to the KPP equation, Ann. Inst. H. Poincare ... More