Results for "Dimitri N. Laikov"

total 63420took 0.70s
Additive atomic approximation for relativistic effects: a two-component Hamiltonian for molecular electronic structure calculationsNov 20 2018An approximate relativistic two-component Hamiltonian for use in molecular electronic structure calculations is derived in the form of a sum of fixed atom-centered kinetic and spin-orbit operators added to the non-relativistic Hamiltonian. Starting from ... More
Atomic basis functions for molecular electronic structure calculationsAug 16 2018Electronic structure methods for accurate calculation of molecular properties have a high cost that grows steeply with the problem size, therefore, it is helpful to have the underlying atomic basis functions that are less in number but of higher quality. ... More
A reversible numerical integrator of the isokinetic equations of motionSep 17 2017Oct 30 2018An explicit second-order numerical method to integrate the isokinetic equations of motion is derived by fitting circular arcs through every three consecutive points of the discretized trajectory, so that the tangent and the curvature satisfy the equations ... More
Combination of many-body and density-functional theoriesJun 14 2011A framework for developing new approximate electronic structure methods is presented, in which the correlation energy of a many-electron system in the ground state is computed as in the single-reference second-order many-body perturbation theory but with ... More
Atomic effective potentials for starting molecular electronic structure calculationsFeb 08 2019Molecular electronic structure calculations can be easily started by diagonalizing a one-electron Hamiltonian based on a sum of fixed atomic effective potentials. For the latter, we have found compact analytic forms in terms of a few Gaussian functions ... More
A new parametrizable model of molecular electronic structureJun 23 2011Aug 29 2011A new electronic structure model is developed in which the ground state energy of a molecular system is given by a Hartree-Fock-like expression with parametrized one- and two-electron integrals over an extended (minimal + polarization) set of orthogonalized ... More
"New Cybernetics and the Application of its Principles in Physics" and "Comment on "Quantum Solution to the Arrow-of-Time Dilemma" of L. Maccone arXiv:0802.0438"Nov 13 2009Sep 18 2013The first paper: We describe principles of new cybernetics and use these principles for resolution of basic physical paradoxes. It demonstrates universality of the principles of new cybernetics. The second paper: recent letter by Maccone presents a solution ... More
Stable marked point processesAug 03 2007In many contexts such as queuing theory, spatial statistics, geostatistics and meteorology, data are observed at irregular spatial positions. One model of this situation involves considering the observation points as generated by a Poisson process. Under ... More
Covariance matrix estimation and linear process bootstrap for multivariate time series of possibly increasing dimensionJun 02 2015Multivariate time series present many challenges, especially when they are high dimensional. The paper's focus is twofold. First, we address the subject of consistently estimating the autocovariance sequence; this is a sequence of matrices that we conveniently ... More
Extending the n=2 Ruddlesden-Popper Solid Solution La2-2xSr1+2xMn2O7 Beyond x=0.5: Synthesis of Mn4+-rich CompoundsApr 06 1999We report the synthesis and room temperature crystal structures of the heretofore unknown, metastable manganites La2-2xSr1+2xMn2O7+delta (0.5 < x < 0.9) via high-temperature (T=1650 C) quenching followed by low-temperature (T=400 C) annealing to fill ... More
Enumerating Subgraph Instances Using Map-ReduceAug 02 2012Nov 21 2012The theme of this paper is how to find all instances of a given "sample" graph in a larger "data graph," using a single round of map-reduce. For the simplest sample graph, the triangle, we improve upon the best known such algorithm. We then examine the ... More
Waveform Design for Secure SISO Transmissions and MulticastingJun 03 2013Wireless physical-layer security is an emerging field of research aiming at preventing eavesdropping in an open wireless medium. In this paper, we propose a novel waveform design approach to minimize the likelihood that a message transmitted between trusted ... More
A Message Passing Strategy for Decentralized Connectivity Maintenance in Agent RemovalNov 01 2013In a multi-agent system, agents coordinate to achieve global tasks through local communications. Coordination usually requires sufficient information flow, which is usually depicted by the connectivity of the communication network. In a networked system, ... More
Multispectral Deep Neural Networks for Pedestrian DetectionNov 08 2016Multispectral pedestrian detection is essential for around-the-clock applications, e.g., surveillance and autonomous driving. We deeply analyze Faster R-CNN for multispectral pedestrian detection task and then model it into a convolutional network (ConvNet) ... More
Convolved subsampling estimation with applications to block bootstrapJun 22 2017The block bootstrap approximates sampling distributions from dependent data by resampling data blocks. A fundamental problem is establishing its consistency for the distribution of a sample mean, as a prototypical statistic. We use a structural relationship ... More
The pseudorelativistic Hartree equation with a general nonlinearity: existence, non existence and variational identitiesJun 05 2012We prove several existence and non existence results of solitary waves for a class of nonlinear pseudo-relativistic Hartree equations with general nonlinearities. We use variational methods and some new variational identities involving the half Laplacian. ... More
Divisors of shifted primesMay 01 2009May 15 2010We bound from below the number of shifted primes p+s<x that have a divisor in a given interval (y,z]. Kevin Ford has obtained upper bounds of the expected order of magnitude on this quantity as well as lower bounds in a special case of the parameters ... More
Localized factorizations of integersSep 05 2008May 28 2013We determine the order of magnitude of H^{(k+1)}(x,\vec{y},2\vec{y}), the number of integers up to x that are divisible by a product d_1...d_k with y_i<d_i\le 2y_i, when the numbers \log y_1,...,\log y_k have the same order of magnitude and k\ge 2. This ... More
On the achromatic number of signed graphsFeb 13 2019In this paper, we generalize the concept of complete coloring and achromatic number to 2-edge-colored graphs and signed graphs. We give some useful relationships between different possible definitions of such achromatic numbers and prove that computing ... More
Exploring the LHC Landscape with DileptonsSep 28 2016Oct 07 2016The dilepton decay channels provide clean signatures and are an ideal hunting ground for high mass resonant, like Z', or non-resonant, like contact interactions or extra dimensions, searches at the LHC. The production of high invariant mass opposite sign ... More
Asymptotic expansions of the inverse of the Beta distributionNov 11 2016In this paper, we shall study the asymptotic behaviour of the $p$-inverse of the Beta distribution, i.e. the quantity $q$ defined implicitly by $\int_0^q t^{a - 1} (1 - t)^{b - 1} \text{d} t = p B (a, b)$, as a function of the first parameter $a$. In ... More
The migration of gas giant planets in gravitationally unstable discsAug 04 2015Planets form in the discs of gas and dust that surround young stars. It is not known whether gas giant planets on wide orbits form the same way as Jupiter or by fragmentation of gravitationally unstable discs. Here we show that a giant planet, which has ... More
(Non)triviality of Pure Spinors and Exact Pure Spinor - RNS MapOct 26 2008Nov 21 2008All the BRST-invariant operators in pure spinor formalism in $d=10$ can be represented as BRST commutators, such as $V=\lbrace{Q_{brst}},{{\theta_{+}}\over{\lambda_{+}}}V\rbrace$ where $\lambda_{+}$ is the U(5) component of the pure spinor transforming ... More
Enumeration of ramified coverings of the sphere and 2-dimensional gravityJun 13 2005Let A be the algebra generated by the power series \sum n^{n-1} q^n/n! and \sum n^n q^n /n! . We prove that many natural generating functions lie in this algebra: those appearing in graph enumeration problems, in the intersection theory of moduli spaces ... More
Counting ramified coverings and intersection theory on Hurwitz spaces II (Local structure of Hurwitz spaces and combinatorial results)Apr 18 2003The Hurwitz space is a compactification of the space of rational functions of a given degree. We study the intersection of various strata of this space with its boundary. A study of the cohomology ring of the Hurwitz space then allows us to obtain recurrence ... More
A simple bound for the variation at closest approach of a small body and star due to general relativityApr 07 2014As a comet, asteroid or planet approaches its parent star, the orbit changes shape due to the curvature of spacetime. For comets in particular, the deviation at the pericentre may noticeably change their ephemerides and affect the dynamics of outgassing, ... More
On homotopy types modelized by strict \infty-groupoidsJun 13 2012Sep 26 2012The purpose of this text is the study of the class of homotopy types which are modelized by strict \infty-groupoids. We show that the homotopy category of simply connected \infty-groupoids is equivalent to the derived category in homological degree greater ... More
Lax formal theory of monads, monoidal approach to bicategorical structures and generalized operadsDec 15 2014Apr 21 2015Generalized operads, also called generalized multicategories and $T$-monoids, are defined as monads within a Kleisli bicategory. With or without emphasizing their monoidal nature, generalized operads have been considered by numerous authors in different ... More
On multiplicative functions which are small on averageNov 11 2011Jun 17 2013Let $f$ be a completely multiplicative function that assumes values inside the unit disc. We show that if $\sum_{n<x} f(n) \ll x/(\log x)^A$, $x>2$, for some $A>2$, then either $f(p)$ is small on average or $f$ pretends to be $\mu(n)n^{it}$ for some $t$. ... More
A strong collapse increasing the geometric simplicial Lusternik-Schnirelmann categoryOct 26 2017In [3], after defining notions of LS category in the simplicial context, the authors show that the geometric simplicial LS category is non-decreasing under strong collapses. However, they do not give examples where it increases strictly, but they conjecture ... More
Pretentious multiplicative functions and the prime number theorem for arithmetic progressionsMar 03 2012Mar 13 2013Building on the concept of pretentious multiplicative functions, we give a new and largely elementary proof of the best result known on the counting function of primes in arithmetic progressions.
Full Stark Control of Polariton States on a Spin-Orbit HypersphereJun 07 2016Nov 21 2016The orbital angular momentum and the polarisation of light are physical quantities widely investigated for classical and quantum information processing. In this work we propose to take advantage of strong light-matter coupling, circular-symmetric confinement, ... More
Ground Ring of Alpha-Symmetries and Sequence of RNS String TheoriesMay 29 2009Jun 03 2009We construct a sequence of nilpotent BRST charges in RNS superstring theory, based on new gauge symmetries on the worldsheet, found in this paper. These new local gauge symmetries originate from the global nonlinear space-time $\alpha$-symmetries, shown ... More
Multisymplectic formulation of vielbein gravity. De Donder-Weyl formulation, Hamiltonian (n-1)-formsApr 14 2014Dec 11 2015We consider the De Donder-Weyl (DW) Hamiltonian formulation of the Palatini action of vielbein gravity formulated in terms of the solder form and spin connection, which are treated as independent variables. The basic geometrical constructions necessary ... More
Asymptotic expansions of the inverse of the Beta distributionNov 11 2016Sep 21 2017In this work in progress, we study the asymptotic behaviour of the $p$-quantile of the Beta distribution, i.e. the quantity $q$ defined implicitly by $\int_0^q t^{a - 1} (1 - t)^{b - 1} \text{d} t = p B (a, b)$, as a function of the first parameter $a$. ... More
The Long-Term Dynamical Evolution of Planetary SystemsNov 26 2013This chapter concerns the long-term dynamical evolution of planetary systems from both theoretical and observational perspectives. We begin by discussing the planet-planet interactions that take place within our own Solar System. We then describe such ... More
Least quantile regression via modern optimizationOct 31 2013Nov 19 2014We address the Least Quantile of Squares (LQS) (and in particular the Least Median of Squares) regression problem using modern optimization methods. We propose a Mixed Integer Optimization (MIO) formulation of the LQS problem which allows us to find a ... More
On the Efficiency of Influence-and-Exploit Strategies for Revenue Maximization under Positive ExternalitiesOct 10 2011We study the problem of revenue maximization in the marketing model for social networks introduced by (Hartline, Mirrokni, Sundararajan, WWW '08). We restrict our attention to the Uniform Additive Model and mostly focus on Influence-and-Exploit (IE) marketing ... More
On Noncommutativity in String Theory and D-BranesFeb 28 2002Mar 08 2002By considering the B-field dynamical and studying its interaction with Ramond-Ramond (RR) background we observe the breaking of the B-field gauge symmetry in the effective action. This effect takes place due to non-perturbative coupling of the B-field ... More
Efficient and Global Optimization-Based Smoothing Methods for Mixed-Volume MeshesJun 10 2013Jul 08 2013Some methods based on simple regularizing geometric element transformations have heuristically been shown to give runtime efficient and quality effective smoothing algorithms for meshes. We describe the mathematical framework and a systematic approach ... More
Subjects classification from high-dimensional and small-sample size datasets using a strategy based on Clustering Variables around Latent Components (CLV) methodJun 14 2017High-dimensional complex systems can be studied through multivariate analysis, as Principal Component Analysis, however large samples of observations frequently are needed for it. Here it is examined a method for small samples based on clustering variables ... More
Random Walks that Find Perfect Objects and the Lovász Local LemmaJun 02 2014Apr 09 2015We give an algorithmic local lemma by establishing a sufficient condition for the uniform random walk on a directed graph to reach a sink quickly. Our work is inspired by Moser's entropic method proof of the Lov\'{a}sz Local Lemma (LLL) for satisfiability ... More
On the symmetry of finite sums of exponentialsOct 03 2018In this note we are interested in the rich geometry of the graph of a curve $\gamma_{a,b}: [0,1] \rightarrow \mathbb{C}$ defined as \begin{equation*} \gamma_{a,b}(t) = \exp(2\pi i a t) + \exp(2\pi i b t), \end{equation*} in which $a,b$ are two different ... More
Exactness of Cuntz-Pimsner C*-algebrasNov 02 1999Let H be a full Hilbert bimodule over a C*-algebra A. We show that the Cuntz-Pimsner C*-algebra associated to H is exact if and only if A is exact. Using this result, we give alternative proofs for exactness of reduced amalgamated free products of exact ... More
Momentum modes of M5-branes in a 2d spaceMay 30 2012Jun 06 2012We study M5 branes by considering the selfdual strings parallel to a plane. With the internal oscillation frozen, each selfdual string gives a 5d SYM field. All selfdual strings together give a 6d field with 5 scalars, 3 gauge degrees of freedom and 8 ... More
Scaling invariance in finance II: Path-dependent contingent claimsJul 13 1999This article is the second one in a series on the use of scaling invariance in finance. In the first article (cond-mat/9906048), we introduced a new formalism for the pricing of derivative securities, which focusses on tradable objects only, and which ... More
The Chromatic Number of Random Regular GraphsJul 11 2004Given any integer d >= 3, let k be the smallest integer such that d < 2k log k. We prove that with high probability the chromatic number of a random d-regular graph is k, k+1, or k+2, and that if (2k-1) \log k < d < 2k \log k then the chromatic number ... More
The Asymptotic Order of the k-SAT ThresholdSep 26 2002Form a random k-SAT formula on n variables by selecting uniformly and independently m=rn clauses out of all 2^k (n choose k) possible k-clauses. The Satisfiability Threshold Conjecture asserts that for each k there exists a constant r_k such that, as ... More
Violations of local equilibrium and linear response in classical lattice theoriesOct 17 2001We study the dynamics of $\phi^4$ theory and the FPU $\beta$ model under thermal gradients, from first principles. We analyze quantitatively how local equilibrium and linear response are violated, paying special care to how we find observables that unambiguously ... More
Non-Equilibrium Steady States and Transport in the Classical Lattice $φ^4$ TheoryNov 21 1999We study the classical non-equilibrium statistical mechanics of scalar field theory on the lattice. Steady states are analyzed near and far from equilibrium. The bulk thermal conductivity is computed, including its temperature dependence. We examine the ... More
Non-Equilibrium Statistical Mechanics of Classical Lattice $φ^4$ Field TheoryFeb 15 2000Classical $\phi^4$ theory in weak and strong thermal gradients is studied on the lattice in (1+1) dimensions. Classical $\phi^4$ theory in weak and strong thermal gradients is studied on the lattice in (1+1) dimensions. The steady state physics of the ... More
A geometric mesh smoothing algorithm related to damped oscillationsNov 17 2014Sep 27 2016We introduce a smoothing algorithm for triangle, quadrilateral, tetrahedral and hexahedral meshes whose centerpiece is a simple geometric triangle transformation. The first part focuses on the mathematical properties of the element transformation. In ... More
The effect of radiative feedback on disc fragmentationOct 26 2016Protostellar discs may become massive enough to fragment producing secondary low-mass objects: planets, brown dwarfs and low-mass stars. We study the effect of radiative feedback from such newly-formed secondary objects using radiative hydrodynamic simulations. ... More
Type transition of simple random walks on randomly directed regular latticesApr 24 2012Jan 30 2014Simple random walks on a partially directed version of $\mathbb{Z}^2$ are considered. More precisely, vertical edges between neighbouring vertices of $\mathbb{Z}^2$ can be traversed in both directions (they are undirected) while horizontal edges are one-way. ... More
Curved space-times by crystallization of liquid fiber bundlesAug 31 2015Sep 25 2015Motivated by the search for a Hamiltonian formulation of Einstein equations of gravity which depends in a minimal way on choices of coordinates, nor on a choice of gauge, we develop a multisymplectic formulation on the total space of the principal bundle ... More
Proximal Algorithms and Temporal Differences for Large Linear Systems: Extrapolation, Approximation, and SimulationOct 18 2016In this paper we consider large linear fixed point problems and solution with proximal algorithms. We show that, under certain assumptions, there is a close connection between proximal iterations, which are prominent in numerical analysis and optimization, ... More
Changes of variables in ELSV-type formulasFeb 21 2006Jun 25 2007In [5] I.P. Goulden, D.M. Jackson, and R. Vakil formulated a conjecture relating certain Hurwitz numbers (enumerating ramified coverings of the sphere) to the intersection theory on a conjectural Picard variety. We are going to use their formula to study ... More
A group action on Losev-Manin cohomological field theoriesSep 04 2009We discuss an analog of the Givental group action for the space of solutions of the commutativity equation. There are equivalent formulations in terms of cohomology classes on the Losev-Manin compactifications of genus 0 moduli spaces; in terms of linear ... More
Galaxy Bulges and Elliptical Galaxies - Lecture NotesAug 10 2012Our knowledge on the central components of disk galaxies has grown substantially in the past few decades, particularly so in the last. This frantic activity and the complexity of the subject promote confusion in the community. In these notes, I discuss ... More
Secular Evolution and Structural Properties of Stellar Bars in GalaxiesMar 08 2010Apr 20 2011I present results from the modeling of stellar bars in nearly 300 barred galaxies in the local universe through parametric multi-component multi-band image fitting. The surface brightness radial profile of bars is described using a Sersic function, and ... More
Analysis of Path-vector Routing StabilityApr 25 2012Most studies on path-vector routing stability have been conducted empirically by means of ad-hoc analysis of BGP data traces. None of them consider prior specification of an analytic method including the use of stability measurement metrics for the systematic ... More
Sampling-based Gradient Regularization for Capturing Long-Term Dependencies in Recurrent Neural NetworksJun 24 2016Vanishing (and exploding) gradients effect is a common problem for recurrent neural networks with nonlinear activation functions which use backpropagation method for calculation of derivatives. Deep feedforward neural networks with many hidden layers ... More
Laplacian smoothing revisitedJun 17 2014We show that the driving force behind the regularizing effect of Laplacian smoothing on surface elements is the popular mean ratio quality measure. We use these insights to provide natural generalizations to polygons and polyhedra. The corresponding functions ... More
Join and slices for strict $\infty$-categoriesJul 03 2016Mar 14 2017The goal of this paper is to develop a theory of join and slices for strict $\infty$-categories. To any pair of strict $\infty$-categories, we associate a third one that we call their join. This operation is compatible with the usual join of categories ... More
Metamagnetism and soliton excitations in the modulated ferromagnetic Ising chain CoV2O6Aug 23 2010Sep 06 2011We report a combination of physical property and neutron scattering measurements for polycrystalline samples of the one-dimensional spin chain compound CoV2O6. Heat capacity measurements show that an effective S = 1/2 state is found at low temperatures ... More
Scale-invariance and contingent claim pricingJun 03 1999Prices of tradables can only be expressed relative to each other at any instant of time. This fundamental fact should therefore also hold for contigent claims, i.e. tradable instruments, whose prices depend on the prices of other tradables. We show that ... More
The homotopy type of the $\infty$-category associated to a simplicial complexMar 09 2015This paper is part of a series of papers about homotopy theory of strict $n$-categories. In the first paper of this series, we gave conditions that guarantee the existence of a Thomason model category structure on the category of strict $n$-categories. ... More
Towards a Thomason model structure on the category of strict n-categoriesMay 22 2013Apr 18 2014The purpose of this article is to present ideas towards obtaining a model category structure on the category of small strict n-categories, generalizing the one obtained by Thomason on ordinary categories. Following ideas of Grothendieck and Cisinski, ... More
The two possible values of the chromatic number of a random graphJun 12 2007Given d \in (0,infty) let k_d be the smallest integer k such that d < 2k\log k. We prove that the chromatic number of a random graph G(n,d/n) is either k_d or k_d+1 almost surely.
Explosion, implosion, and moments of passage times for continuous-time Markov chains: a semimartingale approachFeb 05 2012Jun 14 2012We establish general theorems quantifying the notion of recurrence --- through an estimation of the moments of passage times --- for irreducible continuous-time Markov chains on countably infinite state spaces. Sharp conditions of occurrence of the phenomenon ... More
Product Measure Approximation of Symmetric Graph PropertiesFeb 26 2015In the study of random structures we often face a trade-off between realism and tractability, the latter typically enabled by assuming some form of independence. In this work we initiate an effort to bridge this gap by developing tools that allow us to ... More
High-contrast Ultrabroadband Frontend Source for High Intensity Few-Cycle LasersSep 09 2011An ultrabroadband seed source for high-power, high-contrast OPCPA systems at 800 nm is presented. The source is based on post compression in a hollow-core fiber followed by crossed polarized waves (XPW) filtering and is capable of delivering 80$\mu$J, ... More
The formation of brown dwarfs in discs: Physics, numerics, and observationsSep 23 2010A large fraction of brown dwarfs and low-mass stars may form by gravitational fragmentation of relatively massive (a few 0.1 Msun), extended (a few hundred AU) discs around Sun-like stars. We present an ensemble of radiative hydrodynamic simulations that ... More
Random k-SAT: Two Moments Suffice to Cross a Sharp ThresholdOct 09 2003Many NP-complete constraint satisfaction problems appear to undergo a "phase transition'' from solubility to insolubility when the constraint density passes through a critical threshold. In all such cases it is easy to derive upper bounds on the location ... More
On the exact number of bifurcation branches from a multiple eigenvalueSep 01 2005We study local bifurcation from an eigenvalue with multiplicity greater than one for a class of semilinear elliptic equations. We evaluate the exact number of bifurcation branches of non trivial solutions and we compute the Morse index of the solutions ... More
Carleman estimates for singular parabolic equations with interior degeneracy and non smooth coefficientsJul 28 2015Nov 18 2015We establish Carleman estimates for singular/degenerate parabolic Dirichlet problems with degeneracy and singularity occurring in the interior of the spatial domain. Our results are completely new, since this situation is not covered by previous contributions ... More
Bulk Properties of Anharmonic Chains in Strong Thermal Gradients: Non-Equilibrium $φ^4$ TheoryOct 09 1999We study nonequilibrium properties of a one-dimensional lattice Hamiltonian with quartic interactions in strong thermal gradients. Nonequilibrium temperature profiles, T(x), are found to develop significant curvature and boundary jumps. From the determination ... More
Classical $φ^4$ Lattice Field Theory in Strong Thermal GradientsNov 22 1999The dynamics of classical $\phi^4$ theory under weak and strong thermal gradients is studied. We obtain the thermal conductivity of the theory including its temperature dependence. Under moderately strong thermal gradients, the temperature profiles become ... More
A geometric mesh smoothing algorithm related to damped oscillationsNov 17 2014Aug 28 2017We introduce a smoothing algorithm for triangle, quadrilateral, tetrahedral and hexahedral meshes whose centerpiece is a simple geometric triangle transformation. The first part focuses on the mathematical properties of the element transformation. In ... More
Efficient Mesh Optimization Using the Gradient Flow of the Mean VolumeFeb 25 2013Jan 30 2014The signed volume function for polyhedra can be generalized to a mean volume function for volume elements by averaging over the triangulations of the underlying polyhedron. If we consider these up to translation and scaling, the resulting quotient space ... More
The fractional Hartree equation without the Ambrosetti-Rabinowitz conditionJun 27 2016We consider a class of pseudo-relativistic Hartree equations in presence of general nonlinearities not satisfying the Ambrosetti-Rabinowitz condition. Using variational methods based on critical point theory, we show the existence of two non trivial signed ... More
A fractional eigenvalue problem in $\mathbb{R}^N$Jun 18 2015We prove that a linear fractional operator with an asymptotically constant lower order term in the whole space admits eigenvalues.
Focused Stochastic Local Search and the Lovász Local LemmaJul 28 2015Aug 15 2015We develop tools for analyzing focused stochastic local search algorithms. These are algorithms which search a state space probabilistically by repeatedly selecting a constraint that is violated in the current state and moving to a random nearby state ... More
All generating sets of all property T von Neumann algebras have free entropy dimension $\leq 1$Mar 28 2006Mar 29 2006Suppose $N$ is a diffuse, property T von Neumann algebra and X is an arbitrary finite generating set of selfadjoint elements for N. By using rigidity/deformation arguments applied to representations of N in full matrix algebras, we deduce that the microstate ... More
Photo-enhanced metastable c-axis electrodynamics in stripe ordered cuprate La$_{1.885}$Ba$_{0.115}$CuO$_{4}$Jan 28 2019Quantum materials are amenable to non-equilibrium manipulation with light, enabling modification and control of macroscopic properties. Light-based augmentation of superconductivity is particularly intriguing. Copper-oxide superconductors exhibit complex ... More
Charge order at the frontier between the molecular and solid states in Ba3NaRu2O9Sep 06 2011Mar 28 2012We show that the valence electrons of Ba3NaRu2O9, which has a quasi-molecular structure, completely crystallize below 210 K. Using an extended Hubbard model, we show that the charge ordering instability results from long-range Coulomb interactions. However, ... More
Local moments and symmetry breaking in metallic PrMnSbOJun 02 2010We report a combined experimental and theoretical investigation of the layered antimonide PrMnSbO which is isostructural to the parent phase of the iron pnictide superconductors. We find linear resistivity near room temperature and Fermi liquid-like T^{2} ... More
A valence bond liquid on the honeycomb latticeOct 29 2013Nov 14 2013The honeycomb lattice material Li2RuO3 undergoes a dimerization of Ru4+ cations on cooling below 270C, where the magnetic susceptibility vanishes. We use density functional theory calculations to show that this reflects the formation of a 'valence bond ... More
Models of Saturn's protoplanetary disk forming in-situ its regular satellites and innermost rings before the planet is fully formedJan 22 2019We fit an isothermal oscillatory density model of Saturn's protoplanetary disk to the present-day major satellites and innermost rings D/C and we determine the radial scale length of the disk, the equation of state and the central density of the primordial ... More
Topology of Gleason Parts in maximal ideal spaces with no analytic discsFeb 14 2019We strengthen, in various directions, the theorem of Garnett that every sigma-compact, completely regular space X occurs as a Gleason part for some uniform algebra. In particular, we show that the uniform algebra can always be chosen so that its maximal ... More
A simple model to describe intrinsic stellar noise for exoplanet detection around red giantsOct 27 2016In spite of the huge advances in exoplanet research provided by the NASA Kepler Mission, there remain only a small number of transit detections around evolved stars. Here we present a reformulation of the noise properties of red-giant stars, where the ... More
Tunable plasmonic reflection by bound 1D electron states in a 2D Dirac metalFeb 10 2016Jun 15 2016We show that surface plasmons of a two-dimensional Dirac metal such as graphene can be reflected by line-like perturbations hosting one-dimensional electron states. The reflection originates from a strong enhancement of the local optical conductivity ... More
Current oscillations in Vanadium Dioxide: evidence for electrically triggered percolation avalanchesSep 08 2011In this work, we experimentally and theoretically explore voltage controlled oscillations occurring in micro-beams of vanadium dioxide. These oscillations are a result of the reversible insulator to metal phase transition in vanadium dioxide. Examining ... More
Quantum simulations and many-body physics with lightApr 15 2016In this review we discuss the works in the area of quantum simulation and many-body physics with light, from the early proposals on equilibrium models to the more recent works in driven dissipative platforms. We start by describing the founding works ... More
Pinning quantum phase transition of photons in a hollow-core fiberMar 24 2011We show that a pinning quantum phase transition for photons could be observed in a hollow-core one-dimensional fiber loaded with a cold atomic gas. Utilizing the strong light confinement in the fiber, a range of different strongly correlated polaritonic ... More
Reproducing spin lattice models in strongly coupled atom-cavity systemsFeb 04 2008Sep 30 2008In an array of coupled cavities where the cavities are doped with an atomic V-system, and the two excited levels couple to cavity photons of different polarizations, we show how to construct various spin models employed in characterizing phenomena in ... More
Implementing universal quantum gates in coupled cavitiesJul 26 2007We study a linear array of coupled cavities interacting with two level systems and show how to construct individually addressable qubits in this system from the long-lived atom-photon excitations (polaritons) at each site. We derive the system dynamics ... More
Decentralized Abstractions For Multi-Agent Systems Under Coupled ConstraintsJun 17 2015Aug 22 2016The goal of this report is to define abstractions for multi-agent systems with feedback interconnection in their dynamics. In the proposed decentralized framework, we specify a finite or countable transition system for each agent which only takes into ... More
Exact Solutions of the Isothermal Lane--Emden Equation with Rotation and Implications for the Formation of Planets and SatellitesJun 21 2007Nov 06 2008We have derived exact solutions of the isothermal Lane--Emden equation with and without rotation in a cylindrical geometry. The corresponding hydrostatic equilibria are most relevant to the dynamics of the protosolar nebula before and during the stages ... More
The Case Against Dark Matter and Modified Gravity: Flat Rotation Curves Are a Rigorous Requirement in Rotating Self-Gravitating Newtonian Gaseous DisksOct 19 2015Oct 24 2015By solving analytically the various types of Lane-Emden equations with rotation, we have discovered two new coupled fundamental properties of rotating, self-gravitating, gaseous disks in equilibrium: Isothermal disks must, on average, exhibit strict power-law ... More