Results for "Evan Berkowitz"

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Supergravity from Gauge TheoryAug 05 2016Gauge/gravity duality is the conjecture that string theories have dual descriptions as gauge theories. Weakly-coupled gravity is dual to strongly-coupled gauge theories, ideal for lattice calculations. I will show precision lattice calculations that confirm ... More
Lattice QCD and Axion CosmologySep 09 2015The Strong CP Problem can be resolved by introducing an additional global symmetry known as Peccei-Quinn symmetry. Once PQ symmetry is broken the associated particle, the QCD axion, is a plausible dark matter candidate. Calculating the cosmological energy ... More
A microscopic description of black hole evaporation via holographyMar 09 2016Jul 03 2016We propose a description of how a large, cold black hole (black zero-brane) in type IIA superstring theory evaporates into freely propagating D0-branes, by solving the dual gauge theory quantitatively. The energy spectrum of emitted D0-branes is parametrically ... More
Multi-channel S-matrices from energy levels in finite boxesNov 09 2012Mar 06 2013We show that for a generic quantum mechanical system with more than one open scattering channel, it is not possible to fully reconstruct the theory's S-matrix from spectral information obtained in large finite volumes with periodic boundary conditions. ... More
Neutrinoless double beta decay from lattice QCDAug 16 2016While the discovery of non-zero neutrino masses is one of the most important accomplishments by physicists in the past century, it is still unknown how and in what form these masses arise. Lepton number-violating neutrinoless double beta decay is a natural ... More
Lattice QCD input for axion cosmologyMay 27 2015One intriguing BSM particle is the QCD axion, which could simultaneously provide a solution to the Strong CP problem and account for some, if not all, of the dark matter density in the universe. This particle is a pNGB of the conjectured Peccei-Quinn ... More
Nuclear condensate and helium white dwarfsNov 05 2011We consider a high density region of the helium phase diagram, where the nuclei form a Bose-Einstein condensate rather than a classical plasma or a crystal. Helium in this phase may be present in helium-core white dwarfs. We show that in this regime there ... More
Vortons in dense quark matterFeb 23 2011Feb 24 2011At large baryon number density, it is likely that the ground state of QCD is a color-flavor-locked phase with a K0 condensate. The CFL+K0 phase is known to support superconducting vortex strings, and it has been previously suggested that it may also support ... More
Thermodynamics of nuclear condensates and phase transitions in white dwarfsJun 05 2012We study the thermodynamics of helium at densities relevant for white dwarf physics. We find evidence that, as the temperature is increased, there is first a first order transition between two superconducting phases followed by a second order transition ... More
Simulating the weak death of the neutron in a femtoscale universe with near-Exascale computingOct 03 2018Oct 10 2018The fundamental particle theory called Quantum Chromodynamics (QCD) dictates everything about protons and neutrons, from their intrinsic properties to interactions that bind them into atomic nuclei. Quantities that cannot be fully resolved through experiment, ... More
Neutrino Emission from Helium White Dwarfs with Condensed CoresMar 05 2012The possibility that ions in a helium white dwarf star are in a Bose-Einstein condensed state has been explored recently. In particular, it has been argued that the resulting novel quantum liquid has a new kind of quasiparticle excitation with a phonon-like ... More
Stable vortex loops in two-species BECsNov 18 2011We consider the creation of stable, stationary closed vortex loops, analogue to the vortons and superconducting cosmic strings, in cold atom BEC's. We explore the parameter region where these solutions are likely to exist and comment on methods to create ... More
Superfluous PhysicsMar 28 2019A superweapon of modern physics superscribes a wide superset of phenomena, ranging from supernumerary rainbows to superfluidity and even possible supermultiplets.
The Stochastic Feynman-Hellmann MethodMay 08 2019The Feynman-Hellmann method, as implemented by Bouchard et al. [1612.06963], was recently employed successfully to determine the nucleon axial charge. A limitation of the method was the restriction to a single operator and a single momentum during the ... More
Chaos in Matrix Models and Black Hole EvaporationFeb 03 2016Mar 17 2016Is the evaporation of a black hole described by a unitary theory? In order to shed light on this question ---especially aspects of this question such as a black hole's negative specific heat---we consider the real-time dynamics of a solitonic object in ... More
An accurate calculation of the nucleon axial charge with lattice QCDApr 04 2017We report on a lattice QCD calculation of the nucleon axial charge, $g_A$, using M\"{o}bius Domain-Wall fermions solved on the dynamical $N_f=2+1+1$ HISQ ensembles after they are smeared using the gradient-flow algorithm. The calculation is performed ... More
A percent-level determination of the nucleon axial coupling from Quantum ChromodynamicsMay 30 2018The $\textit{axial coupling of the nucleon}$, $g_A$, is the strength of its coupling to the $\textit{weak}$ axial current of the Standard Model of particle physics, in much the same way as the electric charge is the strength of the coupling to the electromagnetic ... More
Gauged And Ungauged: A Nonperturbative TestFeb 08 2018We study the thermodynamics of the `ungauged' D0-brane matrix model by Monte Carlo simulation. Our results appear to be consistent with the conjecture by Maldacena and Milekhin.
Nucleon axial coupling from Lattice QCDOct 17 2017We present state-of-the-art results from a lattice QCD calculation of the nucleon axial coupling, $g_A$, using M\"obius Domain-Wall fermions solved on the dynamical $N_f = 2 + 1 + 1$ HISQ ensembles after they are smeared using the gradient-flow algorithm. ... More
Electron shielding of vortons in high-density quark matterDec 06 2011We consider the the effect of the electron cloud about a vorton in the CFL-$K^0$ high-density phase by numerically solving the ultrarelativistic Thomas-Fermi equation about a toroidal charge. Including electrons removes the electric monopole contribution ... More
Job Management and Task BundlingOct 05 2017High Performance Computing is often performed on scarce and shared computing resources. To ensure computers are used to their full capacity, administrators often incentivize large workloads that are not possible on smaller systems. Measurements in Lattice ... More
Three neutrons from Lattice QCDOct 30 2018We present a study on ab-initio calculations of three-neutron correlators from Lattice QCD. We extend the method of baryon blocks to systems of three spacially displaced baryons. This allows the measurement of three-neutron $p$-wave correlators with total ... More
Nuclear Parity Violation from Lattice QCDNov 06 2015The electroweak interaction at the level of quarks and gluons are well understood from precision measurements in high energy collider experiments. Relating these fundamental parameters to Hadronic Parity Violation in nuclei however remains an outstanding ... More
Avoiding Ergodicity Problems in Lattice Discretizations of the Hubbard ModelDec 21 2018The Hubbard model arises naturally when electron-electron interactions are added to the tight-binding descriptions of many condensed matter systems. For instance, the two-dimensional Hubbard model on the honeycomb lattice is central to the ab initio description ... More
Precision lattice test of the gauge/gravity duality at large-$N$Jun 15 2016We pioneer a systematic, large-scale lattice simulation of D0-brane quantum mechanics. The large-$N$ and continuum limits of the gauge theory are taken for the first time at various temperatures $0.4 \leq T \leq 1.0$. As a way to directly test the gauge/gravity ... More
Supergravity from D0-brane Quantum MechanicsJun 15 2016The gauge/gravity duality conjecture claims the equivalence between gauge theory and superstring/M-theory. In particular, the one-dimensional gauge theory of D0-branes and type IIA string theory should agree on properties of hot black holes. Type IIA ... More
Extracting the Single-Particle Gap in Carbon Nanotubes with Lattice Quantum Monte CarloOct 17 2017We show how lattice Quantum Monte Carlo simulations can be used to calculate electronic properties of carbon nanotubes in the presence of strong electron-electron correlations. We employ the path integral formalism and use methods developed within the ... More
A Quantitative Local Limit Theorem for Triangles in Random GraphsOct 05 2016Oct 25 2016In this paper we prove a quantiative local limit theorem for the distribution of the number of triangles in the Erd\H{o}s-Renyi random graph $G(n,p)$, for a fixed $p\in (0,1)$. This proof is an extension of the previous work of Gilmer and Kopparty, who ... More
Two-Nucleon Higher Partial-Wave Scattering from Lattice QCDAug 04 2015We present a determination of nucleon-nucleon scattering phase shifts for l>=0. The S,P,D and F phase shifts for both the spin-triplet and spin-singlet channels are computed for the first time with lattice Quantum ChromoDynamics. This required the design ... More
A Quantitative Local Limit Theorem for Triangles in Random GraphsOct 05 2016In this paper we prove a quantiative local limit theorem for the distribution of the number of triangles in the Erd\H{o}s-Renyi random graph $G(n,p)$, for a fixed $p\in (0,1)$. This proof is an extension of the previous work of Gilmer and Kopparty, who ... More
On the Impossibility of a Poincare-invariant Vacuum State with Unit NormFeb 01 2008Feb 07 2008In the standard construction of Quantum Field Theory, a vacuum state is required. The vacuum is a vector in a separable, infinite-dimensional Hilbert space often referred to as Fock space. By definition the vacuum wavestate depends on nothing and must ... More
Two-nucleon scattering in multiple partial wavesNov 06 2015We determine scattering phase shifts for S,P,D, and F partial wave channels in two-nucleon systems using lattice QCD methods. We use a generalization of Luscher's finite volume method to determine infinite volume phase shifts from a set of finite volume ... More
Two-Nucleon Higher Partial-Wave Scattering from Lattice QCDAug 04 2015Dec 24 2016We present a determination of nucleon-nucleon scattering phase shifts for l >= 0. The S, P, D and F phase shifts for both the spin-triplet and spin-singlet channels are computed with lattice Quantum ChromoDynamics. For l > 0, this is the first lattice ... More
A Local Limit Theorem for Cliques in G(n,p)Nov 08 2018We prove a local limit theorem the number of $r$-cliques in $G(n,p)$ for $p\in(0,1)$ and $r\ge 3$ fixed constants. Our bounds hold in both the $\ell^\infty$ and $\ell^1$ metric. The main work of the paper is an estimate for the characteristic function ... More
Möbius domain-wall fermions on gradient-flowed dynamical HISQ ensemblesJan 26 2017Sep 21 2017We report on salient features of a mixed lattice QCD action using valence M\"{o}bius domain-wall fermions solved on the dynamical $N_f=2+1+1$ HISQ ensembles generated by the MILC Collaboration. The approximate chiral symmetry properties of the valence ... More
Progress in Multibaryon SpectroscopyFeb 25 2019Anchoring the nuclear interaction in QCD is a long-outstanding problem in nuclear physics. While the lattice community has made enormous progress in mesonic physics and single nucleon physics, continuum-limit physical-point multi-nucleon physics has remained ... More
Calm Multi-Baryon OperatorsOct 16 2017Outstanding problems in nuclear physics require input and guidance from lattice QCD calculations of few baryons systems. However, these calculations suffer from an exponentially bad signal-to-noise problem which has prevented a controlled extrapolation ... More
A stability result using the matrix norm to bound the permanentJun 23 2016We prove a stability version of a general result that bounds the permanent of a matrix in terms of its operator norm. More specifically, suppose $A$ is an $n \times n$ matrix over $\mathbb{C}$ (resp. $\mathbb{R}$), and let $\mathcal{P}$ denote the set ... More
Connected-Intersecting Families of GraphsJan 06 2019For a graph property $\mathcal{P}$ and a common vertex set $V = \{1, 2, \ldots, n\}$, a family of graphs on $V$ is \emph{$\mathcal{P}$-intersecting} iff $G \cap H$ satisfies $\mathcal{P}$ for all $G,H$ in the family. Addressing a question of Chung, Graham, ... More
Understanding Galaxy Outflows as the Product of Unstable Turbulent SupportFeb 14 2013The interstellar medium is a multiphase gas in which turbulent support is as important as thermal pressure. Sustaining this configuration requires both continuous turbulent stirring and continuous radiative cooling to match the decay of turbulent energy. ... More
FERMION MASSES IN EXTENDED TECHNICOLOURJan 16 1995Talks presented at Beyond The Standard Model IV Conference, Lake Tahoe, Dec 94: NEW FERMION FAMILIES AND PRECISION ELECTROWEAK DATA: We highlight a trend in the precision electroweak data towards light new physics and argue that some spectra of strongly ... More
Strangelets: Who is Looking, and How?May 11 2006It has been over 30 years since the first suggestion that the true ground state of cold hadronic matter might be not nuclear matter but rather strange quark matter (SQM). Ever since, searches for stable SQM have been proceeding in various forms and have ... More
Holographic QCD & PerfectionJan 25 2007A holographic description of chiral symmetry breaking in the pattern of QCD is reviewed. D7 brane probes are used to include quark fields in a simple non-supersymmetric deformation of the AdS/CFT Correspondence. The axial symmetry breaking is realized ... More
Effects of Reducing Scaffolding in an Undergraduate Electronics LabJun 27 2016Design and scientific investigation are recognized as key components of undergraduate physics laboratory curricula. In light of this, many successful lab programs have been developed to train students to develop these abilities, and students in these ... More
Reinforcement Learning in a Neurally Controlled Robot Using Dopamine Modulated STDPFeb 21 2015Recent work has shown that dopamine-modulated STDP can solve many of the issues associated with reinforcement learning, such as the distal reward problem. Spiking neural networks provide a useful technique in implementing reinforcement learning in an ... More
Applications of a distributional fractional derivative to Fourier analysis and its related differential equationsMay 15 2018A new definition of a fractional derivative has recently been developed, making use of a fractional Dirac delta function as its integral kernel. This derivative allows for the definition of a distributional fractional derivative, and as such paves a way ... More
Combinatorial Sutured TQFT as Exterior AlgebraSep 30 2012The idea of a sutured topological quantum field theory was introduced by Honda, Kazez and Mati\'c (2008). A sutured TQFT associates a group to each sutured surface and an element of this group to each dividing set on this surface. The notion was originally ... More
On the twisted Floer homology of mapping tori of periodic diffeomorphismsOct 12 2009Let K \subset Y be a knot in a three manifold which admits a longitude-framed surgery such that the surgered manifold has first Betti number greater than that of Y. We find a formula which computes the twisted Floer homology of the surgered manifold, ... More
Renormalization Group Flows In The Deformed AdS/CFT CorrespondenceDec 12 2000Dec 21 2000In the AdS/CFT correspondence motion in the radial direction of the AdS space is identified with renormalization group flow in the field theory. For the N=4 Yang-Mills theory this motion is trivial. More interesting examples of renormalization group flow ... More
Decoupling Dynamical Electroweak Symmetry BreakingOct 15 1999The modern precision accelerator data has essentially ruled out the most obvious model of dynamical electroweak symmetry breaking, technicolour. The idea is though well motivated and it is important to construct models compatible with the precision data ... More
QCD Dynamics From M-TheoryMay 10 1998The field theories on the surface of non-supersymmetric D-brane constructions are identified. By moving to M-theory a semi-classical, strong coupling expansion to the IR non-supersymmetric gauge dynamics is obtained. The solution is consistent with the ... More
Softly Broken SQCD: in the Continuum, on the Lattice, on the BraneJul 23 1997Jul 28 1997We review progress in studying the solutions of SQCD in the presence of explicit, soft SUSY breaking terms. Massive N=1 SQCD in the presence of a small gaugino mass leads to a controlled solution which has interesting phase structure with changing theta ... More
Rapidly computable viscous friction and no-slip rigid contact modelsApr 03 2015This article presents computationally efficient algorithms for modeling two special cases of rigid contact---contact with only viscous friction and contact without slip---that have particularly useful applications in robotic locomotion and grasping. Modeling ... More
Strongly Intensive Cumulants: Fluctuation Measures for Systems With Incompletely Constrained VolumesMay 01 2015Sep 04 2015The cumulants of thermal variables are of general interest in physics due to their extensivity and their correspondence with susceptibilities. They become especially significant near critical points of phase transitions where they diverge along with the ... More
A Family of Partially Ordered Sets with Small Balance ConstantSep 18 2017Given a finite poset $\mathcal P$ and two distinct elements $x$ and $y$, we let $\operatorname{pr}_{\mathcal P}(x \prec y)$ denote the fraction of linear extensions of $\mathcal P$ in which $x$ precedes $y$. The balance constant $\delta(\mathcal P)$ of ... More
Non-Equilibrium Steady States in Kac's Model Coupled to a ThermostatMar 29 2016This paper studies the existence, uniqueness and convergence to non-equilibrium steady states in Kac's model with an external coupling. We work in both Fourier distances and Wasserstein distances. Our methods work in the case where the external coupling ... More
Strong Extended Technicolour Interactions and the $Zb\bar{b}$ VertexMar 21 1994LEP precision measurements of the $Zb\bar{b}$ vertex coupling are sufficiently accurate to see the non-oblique corrections from the heavy gauge boson responsible for the large top mass in standard extended tecnicolour models. If the ETC couplings are ... More
V,W and X in Technicolour ModelsNov 30 1993Light techni-fermions and pseudo Goldstone bosons that contribute to the electroweak radiative correction parameters V,W and X may relax the constraints on technicolour models from the experimental values of the parameters S and T. Order of magnitude ... More
What Can the Distribution of Intergalactic Metals Tell us About the History of Cosmological Enrichment?Apr 04 2005I study the relationship between the spatial distribution of intergalactic metals and the masses and ejection energies of the sources that produced them. Over a wide range of models, metal enrichment is dominated by the smallest efficient sources, as ... More
Linear polychromatic colorings of hypercube facesSep 05 2016A coloring of the $\ell$-dimensional faces of $Q_n$ is called $d$-polychromatic if every embedded $Q_d$ has every color on at least one face. Denote by $p_d^\ell$ the maximum number of colors such that any $Q_n$ can be colored in this way. We provide ... More
Metrics for next-generation gravitational-wave detectorsFeb 25 2019Gravitational-wave astrophysics has the potential to be transformed by a global network of longer, colder, and thus more sensitive detectors. This network must be constructed to address a wide range of science goals, involving binary coalescence signals ... More
Duality in Non-Supersymmetric MQCDApr 14 1998Apr 30 1998The curves that describe the M-theoretic extension of type IIA string configurations with non-supersymmetric field theories on their surface exhibit a duality map. The map suggests a continued link between a SU(N) gauge theory with F flavours and an SU(F-N) ... More
Microlensing, or Galactic TwinklingNov 20 1996Microlensing has established itself as a powerful new method for the detection of baryonic dark matter in the Galaxy. The theory of microlensing is sketched and its similarity with the optical effect of twinkling is explained. The bulk of the article ... More
Coexistence of Scale-Invariant States in Incompressible ElastomersFeb 25 2013Nov 01 2013Cavitation and sulcification of soft elastomers are two examples of thresholdless, nonlinear instabilities that evade detection by linearization. I show that the onset of such instabilities can be understood as a kind of phase coexistence between multiple ... More
The current status of neutrino mixingJul 19 2011A brief review of the experimental status of neutrino mixing. The model of neutrino oscillations has now been established with high confidence, with many of the model parameters measured to an accuracy of a few per cent. However, some parameters still ... More
Schur-Concavity for Avoidance of Increasing Subsequences in Block-Ascending PermutationsAug 04 2017Oct 07 2017For integers $a_1, \dots, a_n \ge 0$ and $k \ge 1$, let $\mathcal L_{k+2}(a_1, \dots, a_n)$ denote the set of permutations of $\{1, \dots, a_1+\dots+a_n\}$ whose descent set is contained in $\{a_1, a_1+a_2, \dots, a_1+\dots+a_{n-1}\}$, and which avoids ... More
A regularity criterion for the Navier Stokes equation involving only the middle eigenvalue of the strain tensorOct 16 2017Sep 28 2018This manuscript derives an evolution equation for the symmetric part of the gradient (the strain tensor) in the incompressible Navier Stokes equation on $\mathbb{R}^3$, and proves the existence of $L^2$ mild solutions to this equation. We use this equation ... More
Pair-Production Supernovae: Theory and ObservationSep 07 2006Sep 24 2006I review the physical properties of pair-production supernovae (PPSNe) as well as the prospects for them to be constrained observationally. In very massive (140-260 solar mass) stars, much of the pressure support comes from the radiation field, meaning ... More
Is There a Detectable Vishniac Effect?Feb 08 2000The dominant linear contribution to cosmic microwave background (CMB) fluctuations at small angular scales (less than one arcsec) is a second-order contribution known as the Vishniac or Ostriker-Vishniac effect. This effect is caused by the scattering ... More
Additional Fermion Families and Precision Electroweak DataAug 17 1994The S,T, and U formalism for studying electroweak precision data has recently been updated to include the effects of new light physics and within this analysis the latest LEP and SLC data tightly constrain models of physics beyond the Standard Model. ... More
Quark Condensates in Non-Supersymmetric MQCDJan 23 1998Jun 14 1998A set of non-supersymmetric minimal area embeddings of an M-theory 5-brane are considered. The field theories on the surface of the 5-brane have the field content of N=2 SQCD with fundamental representation matter fields. By suitable choice of curve parameters ... More
Dynamical Generation of the CKM MatrixOct 07 1994We argue that in dynamical models of fermion masses, which explain the three mass scales of the generations of fermions with three separate heavy scales above the electroweak symmetry breaking scale, the off diagonal CKM matrix elements must be generated ... More
Fermion Mass Postdictions in a Generalized Extended Technicolour ScenarioMay 23 1994We review the recent discussion in the literature of one family extended technicolour models with techni-fermion mass spectra compatible with the experimental data for the precision parameters S,T,U,V, W and X and ETC interactions compatible with the ... More
Comment on Cowsik et al.'s "The Dispersion Velocity of Galactic Dark Matter Particles"Jun 25 1996Sep 06 1996In a recent Letter (astro-ph/9605001), Cowsik et al. claim that the best fit value of the velocity dispersion of the Galactic dark matter is 600 kms. This result is obtained by a numerical method of solving the coupled self-gravitation equations, assuming ... More
Critical Population Size for Branching Process Approximation of Probability of Disease ExtinctionNov 14 2016Deterministicmodelstostudythedynamicsofinfectiousdiseaseshavebeenan effective tool for prediction of the persistence of infection. The basic reproduction number R0 has been shown to be a threshold in such models with R0 > 1 a sufficient condition for ... More
Time Evolution of Temperature and Entropy of Various Collapsing Domain WallsJun 12 2011Sep 10 2012We investigate the time evolution of the temperature and entropy of gravitationally collapsing domain walls as seen by an asymptotic observer. In particular, we seek to understand how topology and the addition of a cosmological constant affect the gravitational ... More
Knowledge Representation in Bicategories of RelationsJun 02 2017Nov 01 2017We introduce the relational ontology log, or relational olog, a knowledge representation system based on the category of sets and relations. It is inspired by Spivak and Kent's olog, a recent categorical framework for knowledge representation. Relational ... More
Avoiding algebraic integers of bounded house in orbits of rational functions over cyclotomic closuresAug 14 2016Let $k$ be a number field with cyclotomic closure $k^{\mathrm{cyc}}$, and let $h \in k^{\mathrm{cyc}}(x)$. For $A \ge 1$ a real number, we show that \[ \{ \alpha \in k^{\mathrm{cyc}} : h(\alpha) \in \overline{\mathbb Z} \text{ has house at most } A \} ... More
Linear polychromatic colorings of hypercube facesSep 05 2016Jan 15 2018A coloring of the $\ell$-dimensional faces of $Q_n$ is called $d$-polychromatic if every embedded $Q_d$ has every color on at least one face. Denote by $p^\ell(d)$ the maximum number of colors such that any $Q_n$ can be colored in this way. We provide ... More
A novel approach to fractional calculus: utilizing fractional integrals and derivatives of the Dirac delta functionAug 09 2017Oct 09 2018While the definition of a fractional integral may be codified by Riemann and Liouville, an agreed-upon fractional derivative has eluded discovery for many years. This is likely a result of integral definitions including numerous constants of integration ... More
Molecular Dynamics Simulation Study of Interaction between Model Rough Hydrophobic SurfacesJun 01 2011We study some aspects of hydrophobic interaction between molecular rough and flexible model surfaces. The model we use in this work is based on a model we used previously (Eun, C.; Berkowitz, M. L. J. Phys. Chem. B 2009, 113, 13222-13228), when we studied ... More
Short Range Operator Contributions to $0νββ$ decay from LQCDApr 26 2019The search for neutrinoless double beta decay of nuclei is believed to be one of the most promising means to search for new physics. Observation of this very rare nuclear process, which violates Lepton Number conservation, would imply the neutrino sector ... More
Direct Detection of Stealth Dark Matter through Electromagnetic PolarizabilityMar 13 2015May 28 2015We calculate the spin-independent scattering cross section for direct detection that results from the electromagnetic polarizability of a composite scalar baryon dark matter candidate -- "Stealth Dark Matter", that is based on a dark SU(4) confining gauge ... More
Finite size scaling in minimal walking technicolorJan 30 2012We compare observables to the finite size scaling hypothesis in SU(2) lattice gauge theory with two Dirac fermions in the adjoint representation. The fits that we obtain yield an estimate of the anomalous mass dimension that is consistent with four loop ... More
Particle Filtering on the Audio Localization ManifoldMar 02 2010Mar 02 2010We present a novel particle filtering algorithm for tracking a moving sound source using a microphone array. If there are N microphones in the array, we track all $N \choose 2$ delays with a single particle filter over time. Since it is known that tracking ... More
A New Waveform Consistency Test for Gravitational Wave Inspiral SearchesApr 15 2004Searches for binary inspiral signals in data collected by interferometric gravitational wave detectors utilize matched filtering techniques. Although matched filtering is optimal in the case of stationary Gaussian noise, data from real detectors often ... More
Fast, approximate kinetics of RNA foldingJan 19 2015In this paper, we introduce the software suite, Hermes, which provides fast, novel algorithms for RNA secondary structure kinetics. Using the fast Fourier transform to efficiently compute the Boltzmann probability that a secondary structure S of a given ... More
Multiplicity in 5 Msun StarsOct 14 2010Binary/multiple status can affect stars at all stages of their lifetimes: evolution onto the main sequence, properties on the main sequence, and subsequent evolution. 5 $M_\odot$ stars have provided a wealth of information about the binary properties ... More
From Molecular Cores to Planet-forming Disks: A SIRTF Legacy ProgramMay 08 2003Crucial steps in the formation of stars and planets can be studied only at mid-infrared to far-infrared wavelengths, where SIRTF provides an unprecedented improvement in sensitivity. We will use all three SIRTF instruments (IRAC, MIPS, and IRS) to observe ... More
The First Heroic Decade of MicrolensingApr 14 2003Apr 16 2003We review the fundamentals of vanilla and exotic microlensing. Deviations from the standard form of an achromatic, time-symmetric lightcurve can be caused by the parallax and xallarap effects, finite source size effects and binarity. The pioneering experiments ... More
No Need for Dark Matter in Galaxies?Feb 06 2001Unhappily, there has been a maelstrom of problems for dark matter theories over the last few years and many serious difficulties still have no resolution in sight. This article reviews the evidence for dark matter in galaxies. The haloes built up by hierarchical ... More
Flavour Universal Dynamical Electroweak Symmetry BreakingNov 17 1998The top condensate see-saw mechanism of Dobrescu and Hill allows electroweak symmetry to be broken while deferring the problem of flavour to an electroweak singlet, massive sector. We provide an extended version of the singlet sector that naturally accommodates ... More
Dogs that Don't Bark (The Tale of Baryonic Dark Matter in Galaxies)Nov 13 2002Fifteen years or so ago, it was commonly argued; ``If we want to believe the observations rather than our prejudice, we should take as our best bet that dark haloes are baryonic.'' Such a viewpoint is not often heard today. This change-of-mind has been ... More
Majorana Neutrino Masses Can Save One Family TechnicolourJul 05 1993We make non perturbative estimates of the electroweak radiative correction parameter $S$ in dynamical symmetry breaking models with Majorana neutrino masses. The Majorana masses are treated as perturbations to a Non Local Chiral Model of the strong interactions. ... More
An Extended Technicolor Model With QCD-like Symmetry BreakingSep 11 1995We present a one-doublet extended technicolor model, with all fermions in fundamental representations. The bare lagrangian has no explicit mass terms but generates masses through gauge symmetry breaking by purely QCD-like dynamics. The model generates ... More
The Field Theory of Non-Supersymmetric Brane ConfigurationsAug 22 1997Jan 30 1998We identify the 4D field theories living on the world volume of D4 branes in non-supersymmetric type IIA string theory constructions. They are softly broken N=2 SQCD with the breakings introduced through vevs of the auxilliary fields in the spurion coupling ... More
State of the Art Review for Applying Computational Intelligence and Machine Learning Techniques to Portfolio OptimisationOct 13 2009Computational techniques have shown much promise in the field of Finance, owing to their ability to extract sense out of dauntingly complex systems. This paper reviews the most promising of these techniques, from traditional computational intelligence ... More
Symmetry Principles for String TheoryNov 23 1994The gauge symmetries that underlie string theory arise from inner automorphisms of the algebra of observables of the associated conformal field theory. In this way it is possible to study broken and unbroken symmetries on the same footing, and exhibit ... More
Isolated States and the Classical Phase Spase of 2-d String TheoryNov 14 1991We investigate the classical phase space of 2-d string theory. We derive the linearised covariant equations for the spacetime fields by considering the most general deformation of the energy-momentum tensor which describes $c=1$ matter system coupled ... More
Outer Billiards, Arithmetic Graphs, and the OctagonJun 14 2010Jul 19 2010Outer Billiards is a geometrically inspired dynamical system based on a convex shape in the plane. When the shape is a polygon, the system has a combinatorial flavor. In the polygonal case, there is a natural acceleration of the map, a first return map ... More