Results for "Mark Daley"

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Novelty Search for Deep Reinforcement Learning Policy Network Weights by Action Sequence Edit Metric DistanceFeb 08 2019Reinforcement learning (RL) problems often feature deceptive local optima, and learning methods that optimize purely for reward signal often fail to learn strategies for overcoming them. Deep neuroevolution and novelty search have been proposed as effective ... More
On the Generalizability of Linear and Non-Linear Region of Interest-Based Multivariate Regression Models for fMRI DataFeb 03 2018In contrast to conventional, univariate analysis, various types of multivariate analysis have been applied to functional magnetic resonance imaging (fMRI) data. In this paper, we compare two contemporary approaches for multivariate regression on task-based ... More
Floquet engineering of correlated tunneling in the Bose-Hubbard model with ultracold atomsFeb 08 2016May 18 2016We report on the experimental implementation of tunable occupation-dependent tunneling in a Bose-Hubbard system of ultracold atoms via time-periodic modulation of the on-site interaction energy. The tunneling rate is inferred from a time-resolved measurement ... More
Quantum quench in an atomic one-dimensional Ising chainApr 09 2013Jul 18 2013We study non-equilibrium dynamics for an ensemble of tilted one-dimensional atomic Bose-Hubbard chains after a sudden quench to the vicinity of the transition point of the Ising paramagnetic to anti-ferromagnetic quantum phase transition. The quench results ... More
Observation of many-body long-range tunneling after a quantum quenchDec 10 2013Quantum tunneling constitutes one of the most fundamental processes in nature. We observe resonantly-enhanced long-range quantum tunneling in one-dimensional Mott-insulating Hubbard chains that are suddenly quenched into a tilted configuration. Higher-order ... More
On the Shuffle Automaton Size for WordsJul 29 2009We investigate the state size of DFAs accepting the shuffle of two words. We provide words u and v, such that the minimal DFA for u shuffled with v requires an exponential number of states. We also show some conditions for the words u and v which ensure ... More
Preparation and spectroscopy of a metastable Mott insulator state with attractive interactionsJan 04 2012We prepare and study a metastable attractive Mott insulator state formed with bosonic atoms in a three-dimensional optical lattice. Starting from a Mott insulator with Cs atoms at weak repulsive interactions, we use a magnetic Feshbach resonance to tune ... More
Insights into Quasar UV Spectra Using Unsupervised Clustering AnalysisMar 10 2016Machine learning can provide powerful tools to detect patterns in multi-dimensional parameter space. We use K-means -a simple yet powerful unsupervised clustering algorithm which picks out structure in unlabeled data- to study a sample of quasar UV spectra ... More
Precision Measurements on a Tunable Mott Insulator of Ultracold AtomsJul 09 2011We perform precision measurements on a Mott-insulator quantum state of ultracold atoms with tunable interactions. We probe the dependence of the superfluid-to-Mott-insulator transition on the interaction strength and explore the limits of the standard ... More
Quantum computing with alkaline earth atomsAug 14 2008We present a complete scheme for quantum information processing using the unique features of alkaline earth atoms. We show how two completely independent lattices can be formed for the $^1$S$_0$ and $^3$P$_0$ states, with one used as a storage lattice ... More
Interference of interacting matter wavesDec 28 2008The phenomenon of matter wave interference lies at the heart of quantum physics. It has been observed in various contexts in the limit of non-interacting particles as a single particle effect. Here we observe and control matter wave interference whose ... More
Quantum trajectories and open many-body quantum systemsMay 26 2014The study of open quantum systems has become increasingly important in the past years, as the ability to control quantum coherence on a single particle level has been developed in a wide variety of physical systems. In quantum optics, the study of open ... More
Persistence of energy-dependent localization in the Anderson-Hubbard model with increasing system size and dopingJan 12 2016Non-interacting systems with bounded disorder have been shown to exhibit sharp density of states peaks at the band edge which coincide with an energy range of abruptly suppressed localization. Recent work has shown that these features also occur in the ... More
Quantum Computing and Quantum Simulation with Group-II AtomsJun 28 2011Recent experimental progress in controlling neutral group-II atoms for optical clocks, and in the production of degenerate gases with group-II atoms has given rise to novel opportunities to address challenges in quantum computing and quantum simulation. ... More
Nonreciprocal Quantum Transport at Junctions of Structured LeadsOct 11 2018We propose and analyze a mechanism for rectification of spin transport through a small junction between two spin baths or leads. For interacting baths we show that transport is conditioned on the spacial asymmetry of the quantum junction mediating the ... More
Resonant two-site tunnelling dynamics of bosons in a tilted optical superlatticeNov 16 2018We study the non-equilibrium dynamics of a 1D Bose-Hubbard model in a gradient potential and a superlattice, beginning from a deep Mott insulator regime with an average filling of one particle per site. Studying a quench that is near resonance to tunnelling ... More
Signatures of Many-Body Localization in a Controlled Open Quantum SystemOct 05 2016In the presence of disorder, an interacting closed quantum system can undergo many-body localization (MBL) and fail to thermalize. However, over long times even weak couplings to any thermal environment will necessarily thermalize the system and erase ... More
Spin-models, dynamics and criticality with atoms in tilted optical superlatticesNov 16 2018We show that atoms in tilted optical superlattices provide a platform for exploring coupled spin chains of forms that are not present in other systems. In particular, using a period-2 superlattice in 1D, we show that coupled Ising spin chains with XZ ... More
Interacting Fields and Flows: Magnetic Hot JupitersNov 30 2017We present Magnetohydrodynamic (MHD) simulations of the magnetic interactions between a solar type star and short period hot Jupiter exoplanets, using the publicly available MHD code PLUTO. It has been predicted that emission due to magnetic interactions ... More
Effective three-body interactions via photon-assisted tunneling in an optical latticeNov 07 2013We present a simple, experimentally realizable method to make coherent three-body interactions dominate the physics of an ultracold lattice gas. Our scheme employs either lattice modulation or laser-induced tunneling to reduce or turn off two-body interactions ... More
High velocity gas from the Galactic dark haloNov 13 1998We present the germ of a new model for High Velocity Clouds, derived from the idea that the dark matter halo of our Galaxy is in the form of cold, planetary-mass gas clouds. In this picture HVCs arise as a result of disruptive collisions between dark ... More
What's the value in more moments?May 11 2016The moment-based non-parametric species richness estimator of Chao is one of the most widely used estimators for the number of unobserved species in a sampling experiment. This is due in large part to its simplicity and robustness. This simplicity can ... More
Winds of Massive Magnetic Stars: Interacting Fields and FlowNov 30 2017We present results of 3D numerical simulations of magnetically confined, radiatively driven stellar winds of massive stars, conducted using the astrophysical MHD code Pluto, with a focus on understanding the rotational variability of radio and sub-mm ... More
A martingale view of Blackwell's renewal theorem and its extensions to a general counting processDec 18 2017Dec 24 2018Martingales constitute a basic tool in stochastic analysis; this paper considers their application to counting processes. We use this tool to revisit a renewal theorem and its extensions for various counting processes. We first consider a renewal process ... More
Extreme scattering events and Galactic dark matterFeb 10 1998Mar 20 1998Extreme Scattering Events (ESEs) are attributed to radio-wave refraction by a cloud of free-electrons crossing the line-of-sight. We present a new model in which these electrons form the photo-ionized 'skin' of an underlying cool, self-gravitating cloud ... More
The Cloudy UniverseJul 20 1999Modelling of Extreme Scattering Events suggests that the Galaxy's dark matter is an undetected population of cold, AU-sized, planetary-mass gas clouds. None of the direct observational constraints on this picture -- thermal/non-thermal emission, extinction ... More
A Probabilistic Model of Compound NounsSep 06 1994Compound nouns such as example noun compound are becoming more common in natural language and pose a number of difficult problems for NLP systems, notably increasing the complexity of parsing. In this paper we develop a probabilistic model for syntactically ... More
Thermal stability of cold clouds in galaxy halosJul 02 1999Oct 14 1999We consider the thermal properties of cold, dense clouds of molecular hydrogen and atomic helium. For cloud masses below 10^-1.7 Msun, the internal pressure is sufficient to permit the existence of particles of solid or liquid hydrogen at temperatures ... More
Non-equilibrium dynamics of bosonic atoms in optical lattices: Decoherence of many-body states due to spontaneous emissionSep 01 2010We analyze in detail the heating of bosonic atoms in an optical lattice due to incoherent scattering of light from the lasers forming the lattice. Because atoms scattered into higher bands do not thermalize on the timescale of typical experiments, this ... More
Andreev-like reflections with cold atomsOct 15 2007We propose a setup in which Andreev-like reflections predicted for 1D transport systems could be observed time-dependently using cold atoms in a 1D optical lattice. Using time-dependent Density Matrix Renormalisation Group methods we analyse the wavepacket ... More
Atom-only descriptions of the driven dissipative Dicke modelJan 08 2019We investigate how to describe the dissipative spin dynamics of the driven dissipative Dicke model, describing $N$ two-level atoms coupled to a cavity mode, after adiabatic elimination of the cavity mode. To this end, we derive a Redfield master equation ... More
Dynamical disentangling and cooling of atoms in bilayer optical latticesSep 12 2016We show how experimentally available bilayer lattice systems can be used to prepare quantum many-body states with exceptionally low entropy in one layer, by dynamically disentangling the two layers. This disentangling operation moves one layer - subsystem ... More
Atomic matter-wave revivals with definite atom number in an optical latticeJan 12 2011We study the collapse and revival of interference patterns in the momentum distribution of atoms in optical lattices, using a projection technique to properly account for the fixed total number of atoms in the system. We consider the common experimental ... More
Time-dependent currents of 1D bosons in an optical latticeAug 18 2009Mar 03 2010We analyse the time-dependence of currents in a 1D Bose gas in an optical lattice. For a 1D system, the stability of currents induced by accelerating the lattice exhibits a broad crossover as a function of the magnitude of the acceleration, and the strength ... More
Exotic atom pairs: Repulsively bound states in an optical latticeOct 14 2006We review a recent experiment with ultracold atoms in 3D optical lattices where we have observed a novel kind of bound state of two atoms which is based on repulsive interactions between the particles. These repulsively bound pairs exhibit long lifetimes, ... More
State-dependent lattices for quantum computing with alkaline-earth-metal atomsFeb 07 2011Recent experimental progress with Alkaline-Earth atoms has opened the door to quantum computing schemes in which qubits are encoded in long-lived nuclear spin states, and the metastable electronic states of these species are used for manipulation and ... More
The First Differential of the Functor "Algebraic K-Theory of Spaces"Jun 13 2014In his "Algebraic K-theory of topological spaces II" Waldhausen proved that his functor A(X) splits: There is a canonical map from the stable homotopy of X which has a retraction up to weak equivalence. We adapt Waldhausen's proof to obtain a calculation ... More
Character values and decomposition matrices of symmetric groupsOct 12 2006By exploiting relationships between the values taken by ordinary characters of symmetric groups we prove two theorems in the modular representation theory of the symmetric group. 1. The decomposition matrices of symmetric groups in odd characteristic ... More
Universal Fractional Map and Cascade of Bifurcations Type AttractorsSep 25 2012May 06 2013We modified the way in which the Universal Map is obtained in the regular dynamics to derive the Universal $\alpha$-Family of Maps depending on a single parameter $\alpha > 0$ which is the order of the fractional derivative in the nonlinear fractional ... More
Color superconducting quark matterFeb 05 2001May 04 2001I review recent progress in our understanding of the color superconducting phase of matter above nuclear density, giving particular emphasis to the effort to find observable signatures of the presence of this phase in compact stars.
Status and perspectives of short baseline studiesNov 05 2009The study of flavor changing neutrinos is a very active field of research. I will discuss the status of ongoing and near term experiments investigating neutrino properties at short distances from the source. In the next few years, the Double Chooz, RENO ... More
Ex-house 2D finite-element simulation of the whispering-gallery modes of arbitrarily shaped axisymmetric electromagnetic resonatorsJul 23 2006Mar 20 2007It is described, explicitly, how a popular, commercially-available software package for solving partial-differential-equations (PDEs), as based on the finite-element method (FEM), can be configured to calculate the frequencies and fields of the whispering-gallery ... More
On the theory of symmetric polynomialsMay 09 2014May 13 2014A translation from Russian of the famous paper by Mark Krein "On the theory of symmetric polynomials" published in Math. Sb., vol. 40, no. 3, 1933, pp. 271-283.
Basic Classes of Grammars with ProhibitionFeb 21 2013A practical tool for natural language modeling and development of human-machine interaction is developed in the context of formal grammars and languages. A new type of formal grammars, called grammars with prohibition, is introduced. Grammars with prohibition ... More
Superrecursive Features of Interactive ComputationOct 08 2007Functioning and interaction of distributed devices and concurrent algorithms are analyzed in the context of the theory of algorithms. Our main concern here is how and under what conditions algorithmic interactive devices can be more powerful than the ... More
Unified Foundations for MathematicsMar 10 2004There are different meanings of foundation of mathematics: philosophical, logical, and mathematical. Here foundations are considered as a theory that provides means (concepts, structures, methods etc.) for the development of whole mathematics. Set theory ... More
Algorithmic Problem ComplexityJul 04 2008People solve different problems and know that some of them are simple, some are complex and some insoluble. The main goal of this work is to develop a mathematical theory of algorithmic complexity for problems. This theory is aimed at determination of ... More
Hardware-Oriented Group Solutions for Hard ProblemsOct 15 2004Group and individual solutions are considered for hard problems such as satisfiability problem. Time-space trade-off in a structured active memory provides means to achieve lower time complexity for solutions of these problems.
Elements of the System Theory of TimeJul 12 2002In the paper, elements of the system theory of time are presented, mathematical models for time are constructed, and various properties are deduced from the main principles of the system theory of time. This theory is a far-reaching development of the ... More
Introduction to Projective ArithmeticsOct 15 2010Science and mathematics help people to better understand world, eliminating many inconsistencies, fallacies and misconceptions. One of such misconceptions is related to arithmetic of natural numbers, which is extremely important both for science and everyday ... More
Multi-atoms and monotonicity of generalized Kostka polynomialsApr 07 1998The generalized Kostka polynomials are the Poincare polynomials of isotypic components of certain graded GL(n)-modules. The former satisfy a monotonicity property arising from natural surjections of the corresponding modules. This monotonicity property ... More
A cyclage poset structure for Littlewood-Richardson tableauxApr 07 1998A graded poset structure is defined for the sets of Littlewood-Richardson (LR) tableaux that count the multiplicity of an irreducible GL(n)-module in the tensor product of irreducibles indexed by a sequence of rectangular partitions. This poset generalizes ... More
Understanding Quaternions and the Dirac Belt TrickJan 12 2010May 29 2010The Dirac belt trick is often employed in physics classrooms to show that a $2\pi$ rotation is not topologically equivalent to the absence of rotation whereas a $4\pi$ rotation is, mirroring a key property of quaternions and their isomorphic cousins, ... More
Lyman Alpha Emitting Galaxies as a Probe of ReionizationJun 27 2014Aug 05 2014The Epoch of Reionization (EoR) represents a milestone in the evolution of our Universe. Star-forming galaxies that existed during the EoR likely emitted a significant fraction (~5-40%) of their bolometric luminosity as Lyman Alpha (Lya) line emission. ... More
Does Kolmogorov mean field theory become exact for turbulence above some critical dimension?Mar 25 2001I give three different arguments for an upper critical dimension $d_{max}>3$ above which the 1941 Kolmogorov mean field theory becomes essentially exact, and anomalous scaling vanishes. The first argument concerns the number of degrees of freedom in a ... More
Uniform decision problems and abstract properties of small overlap monoidsOct 26 2009We study the way in which the abstract structure of a small overlap monoid is reflected in, and may be algorithmically deduced from, a small overlap presentation. We show that every C(2) monoid admits an essentially canonical C(2) presentation; by counting ... More
Small overlap monoids: the word problemDec 03 2007We develop a combinatorial approach to the study of semigroups and monoids with finite presentations satisfying small overlap conditions. In contrast to existing geometric methods, our approach facilitates a sequential left-right analysis of words which ... More
Axiomatic Theory of Algorithms: Computability and Decidability in Algorithmic ClassesSep 08 2004Axiomatic approach has demonstrated its power in mathematics. The main goal of this preprint is to show that axiomatic methods are also very efficient for computer science. It is possible to apply these methods to many problems in computer science. Here ... More
Galilean-invariant scalar fields can strengthen gravitational lensingJan 06 2011May 16 2011The mystery of dark energy suggests that there is new gravitational physics on long length scales. Yet light degrees of freedom in gravity are strictly limited by Solar System observations. We can resolve this apparent contradiction by adding a Galilean-invariant ... More
Ordering Dynamics of Topological Defect NetworksDec 22 1997I report on some work in progress on the dynamics of extended objects in field theories after a rapid phase transition, as is relevant in the early Universe. An analytic technique, originally introduced to approximate the dynamics of topological defects ... More
Analytic scaling solutions for cosmic domain wallsMay 16 1996A relativistic generalisation of a well-known method for approximating the dynamics of topological defects in condensed matter is constructed, and applied to the evolution of domain walls in a cosmological context. It is shown that there are self-similar ... More
Where are the Hedgehogs in Nematics?Jan 09 1995In experiments which take a liquid crystal rapidly from the isotropic to the nematic phase, a dense tangle of defects is formed. In nematics, there are in principle both line and point defects (``hedgehogs''), but no point defects are observed until the ... More
Sphalerons and StringsAug 05 1994This work is based on a paper with Margaret James, to appear in Phys Rev D. In it we showed that the dipole moment of the sphaleron has its origin in two components: a ring of electric current circulating around the edge of the sphaleron; and also two ... More
Transverse nucleon structure and multiparton interactionsDec 16 2011The transverse structure of the nucleon as probed in hard exclusive processes plays critical role in the understanding of the structure of the underlying event in hard collisions at the LHC, and multiparton interactions. We summarize results of our recent ... More
Leading twist shadowing, black disk regime and forward hadron productionOct 12 2010We review theory of the leading twist nuclear shadowing, and describe phenomenon of post-selection suppression of leading parton spectrum (effective fractional energy losses) in the proximity of the black disk regime. We argue that $2 \to 2$ mechanism ... More
Quark-gluon densities in the nuclear fragmentation region in heavy ion collisions at LHCFeb 04 2006At the LHC, the leading partons in the nuclei are expected to interact with the maximal possible strength - black disk limit - up to transverse momenta of the order of few GeV. We demonstrate that in this limit the densities of the quark - gluon systems ... More
On the theory of system administrationMar 23 2000This paper describes necessary elements for constructing theoretical models of network and system administration. Armed with a theoretical model it becomes possible to determine best practices and optimal strategies in a way which objectively relates ... More
Spacetimes with Semantics (II), Scaling of agency, semantics, and tenancyMay 07 2015Using Promise Theory as a calculus, I review how to define agency in a scalable way, for the purpose of understanding semantic spacetimes. By following simple scaling rules, replacing individual agents with `super-agents' (sub-spaces), it is shown how ... More
Free adequate semigroupsFeb 02 2009May 08 2009We give an explicit description of the free objects in the quasivariety of adequate semigroups, as sets of labelled directed trees under a natural combinatorial multiplication. The morphisms of the free adequate semigroup onto the free ample semigroup ... More
Magnetic fields in protoplanetary disksApr 07 2007Aug 15 2007Magnetic fields likely play a key role in the dynamics and evolution of protoplanetary discs. They have the potential to efficiently transport angular momentum by MHD turbulence or via the magnetocentrifugal acceleration of outflows from the disk surface, ... More
Early Disk EvolutionDec 09 2003A variety of processes play a role in the evolution of protostellar disks. Here I focus on the uncertain issue of magnetic field-disk coupling and its implications for magnetically-driven turbulence and disk-driven winds. At present it is clear that the ... More
The Balbus-Hawley instability in weakly ionised discsSep 28 1998Mar 31 1999MHD in protostellar discs is modified by the Hall current when the ambipolar diffusion approximation breaks down. Here I examine the Balbus-Hawley (magnetorotational) instability of a weak, vertical magnetic field within a weakly-ionized disc. Vertical ... More
The Eilenberg-Watts theorem in homotopical algebraOct 20 2009Oct 21 2009The object of this paper is to prove that the standard categories in which homotopy theory is done, such as topological spaces, simplicial sets, chain complexes of abelian groups, and any of the various good models for spectra, are all homotopically self-contained. ... More
Metric characterization of apartments in dual polar spacesSep 10 2010Sep 14 2010Let $\Pi$ be a polar space of rank $n$ and let ${\mathcal G}_{k}(\Pi)$, $k\in \{0,\dots,n-1\}$ be the polar Grassmannian formed by $k$-dimensional singular subspaces of $\Pi$. The corresponding Grassmann graph will be denoted by $\Gamma_{k}(\Pi)$. We ... More
Note on half-cube embeddingsMar 04 2009Mar 16 2010Results are well-known
Transformations of Grassman SpacesApr 05 2004Apr 15 2004This is a version of a part of the book ``Transformations of Grassman Spaces'' (in progress). We study transformations of Grassman spaces preserving certain geometrical constructions related to buildings. The next part will be devoted to Grassman spaces ... More
Equality Classes of Nim Positions under Misère PlayJun 07 2015Jul 22 2016We determine the mis\`{e}re equivalence classes of Nim positions under two equivalence relations: one based on playing disjunctive sums with other impartial games, and one allowing sums with partizan games. In the impartial context, the only identifications ... More
Stochastic Spot/Volatility Correlation in Stochastic Volatility Models and Barrier Option PricingApr 15 2014Most models for barrier pricing are designed to let a market maker tune the model-implied covariance between moves in the asset spot price and moves in the implied volatility skew. This is often implemented with a local volatility/stochastic volatility ... More
Stochastic mechanics, trace dynamics, and differential space - a synthesisFeb 25 2006Mar 21 2006It is shown how Adler's trace dynamics can be applied to stochastic mechanics and other complex classical dynamical systems. Emergent non-commutivity due to the fractal nature of sample trajectories is closely related to the fact that the forward and ... More
The generalized Fenyes-Nelson model for free scalar field theoryNov 18 2002The generalized Fenyes--Nelson model of quantum mechanics is applied to the free scalar field. The resulting Markov field is equivalent to the Euclidean Markov field with the times scaled by a common factor which depends on the diffusion parameter. This ... More
Uniformity and Functional Equations for Local Zeta Functions of $\mathfrak{K}$-Split Algebraic GroupsFeb 28 2008Jul 12 2010We study the local zeta functions of an algebraic group $\mathcal{G}$ defined over $\mathfrak{K}$ together with a faithful $\mathfrak{K}$-rational representation $\rho$ for a finite extension $\mathfrak{K}$ of $\mathbb{Q}$. These are given by integrals ... More
Small overlap monoids II: automatic structures and normal formsJun 24 2008Oct 31 2008We show that any finite monoid or semigroup presentation satisfying the small overlap condition C(4) has word problem which is a deterministic rational relation. It follows that the set of lexicographically minimal words forms a regular language of normal ... More
Low Mass Density Wide Field Far-IR/Submillimeter Telescope SystemsJan 13 2000Fundamentally new technology is described for constructing low areal mass density (1kg/m^2), high precision (< 10micron RMS) reflectors scalable to large apertures (10 to 20 meters) for use as the primary element of a telescope system. A large reduction ... More
Model-Independent Measurement of the e+e- -> HZ Cross Section at a Future e+e- Linear Collider using Hadronic Z DecaysSep 09 2015A future e+e- collider, such as the ILC or CLIC, would allow the Higgs sector to be probed with a precision significantly beyond that achievable at the High-Luminosity LHC. A central part of the Higgs programme at an e+e- collider is the model-independent ... More
Characterization of apartments in polar GrassmanniansSep 12 2011Buildings of types $\textsf{C}_n$ and $\textsf{D}_n$ are defined by rank $n$ polar spaces. The associated building Grassmannians are polar and half-spin Grassmannians. Apartments in dual polar spaces and half-spin Grassmannians were characterized in \cite{CKS}. ... More
Non-autonomous stochastic evolution equations and applications to stochastic partial differential equationsJun 27 2008Sep 14 2009In this paper we study the following non-autonomous stochastic evolution equation on a UMD Banach space $E$ with type 2, {equation}\label{eq:SEab}\tag{SE} {{aligned} dU(t) & = (A(t)U(t) + F(t,U(t))) dt + B(t,U(t)) dW_H(t), \quad t\in [0,T], U(0) & = u_0. ... More
Complex WKB Analysis of a PT Symmetric Eigenvalue ProblemMar 09 2007Jun 27 2007The spectra of a particular class of PT symmetric eigenvalue problems has previously been studied, and found to have an extremely rich structure. In this paper we present an explanation for these spectral properties in terms of quantisation conditions ... More
On the smallest L_2 projection of a curve in R^nDec 29 2009Jun 23 2011For a curve T:[0,1] -> R^n, we consider the directions theta in R^n which T "misses" the most and quantify this, as a function of the L_2 norm of T's differential.
Accuracy requirements for the calculation of gravitational waveforms from coalescing compact binaries in numerical relativityFeb 21 2005Apr 11 2005I discuss the accuracy requirements on numerical relativity calculations of inspiraling compact object binaries whose extracted gravitational waveforms are to be used as templates for matched filtering signal extraction and physical parameter estimation ... More
General Relativistic Decompression of Binary Neutron Stars During Dynamic InspiralOct 05 2005Jan 03 2007We investigate the dynamic stability of inspiraling neutron stars by performing multiple-orbit numerical relativity simulations of the binary neutron star inspiral process. By introducing eccentricities in the orbits of the neutron stars, significant ... More
Covering and distortion theorems for spirallike functions with respect to a boundary pointNov 28 2005In this note we obtain some distortion results for spirallike functions with respect to a boundary point. In particular, we find the maximal domain covered by all spirallike functions of order $\beta$.
Microcontroller interrupts for flexible control of time critical tasks in experiments with laser cooled atomsApr 01 2011I detail applications of timer interrupts in a popular micro-controller family to time critical applications in laser-cooling type experiments. I demonstrate a low overhead 1-bit frequency locking scheme and a multichannel experimental sequencer using ... More
A combinatorial proof of a plethystic Murnaghan--Nakayama ruleAug 15 2014Apr 29 2015This article gives a combinatorial proof of a plethystic generalization of the Murnaghan--Nakayama rule. The main result expresses the product of a Schur function with the plethysm $p_r \circ h_n$ as an integral linear combination of Schur functions. ... More
Generalized r-Lah numbersDec 30 2014In this paper, we consider a two-parameter polynomial generalization, denoted by G_{a,b}(n,k;r), of the r-Lah numbers which reduces to these recently introduced numbers when a=b=1. We present several identities for G_{a,b}(n,k;r) that generalize earlier ... More
Generalizations of Bell number formulas of Spivey and MezoDec 02 2014We provide q-generalizations of Spivey's Bell number formula in various settings by considering statistics on different combinatorial structures. This leads to new identities involving q-Stirling numbers of both kinds and q-Lah numbers. As corollaries, ... More
Combinatorial proofs of some Bell number formulasJan 25 2014In this note, we provide bijective proofs of some identities involving the Bell number, as previously requested. Our arguments may be extended to yield a generalization in terms of complete Bell polynomials. We also provide a further interpretation for ... More
On Optimal Transparency in SignalingFeb 03 2019We examine the classic "Beer-Quiche" game from Cho and Kreps (1987), and relax the assumption that the order placed by the sender is completely observable. Under the optimal degree of transparency, the receiver achieves a higher payoff than with full ... More
A Game of MartingalesNov 28 2018Dec 04 2018We consider a two player dynamic game played over $T \leq \infty$ periods. In each period each player chooses any probability distribution with support on $[0,1]$ with a given mean, where the mean is the realized value of the draw from the previous period. ... More
Formal languages and groups as memoryJan 04 2006Oct 19 2007We present an exposition of the theory of finite automata augmented with a multiply-only register storing an element of a given monoid or group. Included are a number of new results of a foundational nature. We illustrate our techniques with a group-theoretic ... More
Word problems recognisable by deterministic blind monoid automataJun 08 2005Jul 27 2005We consider blind, deterministic, finite automata equipped with a register which stores an element of a given monoid, and which is modified by right multiplication by monoid elements. We show that, for monoids M drawn from a large class including groups, ... More