Results for "Alex Andonian"

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Unsupervised Learning from Video with Deep Neural EmbeddingsMay 28 2019Because of the rich dynamical structure of videos and their ubiquity in everyday life, it is a natural idea that video data could serve as a powerful unsupervised learning signal for training visual representations in deep neural networks. However, instantiating ... More
Cross-view Semantic Segmentation for Sensing SurroundingsJun 09 2019Sensing surroundings is ubiquitous and effortless to humans: It takes a single glance to extract the spatial configuration of objects and the free space from the scene. To help machine vision with spatial understanding capabilities, we introduce the View ... More
GANalyze: Toward Visual Definitions of Cognitive Image PropertiesJun 24 2019We introduce a framework that uses Generative Adversarial Networks (GANs) to study cognitive properties like memorability, aesthetics, and emotional valence. These attributes are of interest because we do not have a concrete visual definition of what ... More
Temporal Relational Reasoning in VideosNov 22 2017Jul 25 2018Temporal relational reasoning, the ability to link meaningful transformations of objects or entities over time, is a fundamental property of intelligent species. In this paper, we introduce an effective and interpretable network module, the Temporal Relation ... More
The Algonauts Project: A Platform for Communication between the Sciences of Biological and Artificial IntelligenceMay 14 2019In the last decade, artificial intelligence (AI) models inspired by the brain have made unprecedented progress in performing real-world perceptual tasks like object classification and speech recognition. Recently, researchers of natural intelligence have ... More
Moments in Time Dataset: one million videos for event understandingJan 09 2018Feb 16 2019We present the Moments in Time Dataset, a large-scale human-annotated collection of one million short videos corresponding to dynamic events unfolding within three seconds. Modeling the spatial-audio-temporal dynamics even for actions occurring in 3 second ... More
Coulomb drag in quantum circuitsSep 09 2008Oct 22 2008We study drag effect in a system of two electrically isolated quantum point contacts (QPC), coupled by Coulomb interactions. Drag current exhibits maxima as a function of QPC gate voltages when the latter are tuned to the transitions between quantized ... More
Keldysh technique and non-linear sigma-model: basic principles and applicationsJan 23 2009Apr 27 2009The purpose of this review is to provide a comprehensive pedagogical introduction into Keldysh technique for interacting out-of-equilibrium fermionic and bosonic systems. The emphasis is placed on a functional integral representation of underlying microscopic ... More
On Setting of Heat-and-Mass Transfer Problems under Directed CrystallizationAug 11 2011So far the problem of interface behavior upon phase transition has not yet acquired a satisfactory mathematical formulation due to a variety of the physical phenomena involved. Analytical solutions exist only for elementary problems describing the free ... More
Numerical homotopy continuation for control and online identification of nonlinear systems: the survey of selected resultsJan 26 2013The article gives an overview of the parameter numerical continuation methodology applied to setpoint control and parameter identification of nonlinear systems. The control problems for affine systems as well as general (nonaffine) nonlinear systems are ... More
The Negative Cycle Vectors of Signed Complete GraphsDec 30 2015A signed graph is a graph where the edges are assigned labels of either "$+$" or "$-$". The sign of a cycle in the graph is the product of the signs of its edges. We equip each signed complete graph with a vector whose entries are the number of negative ... More
Stochastic Backpropagation through Mixture Density DistributionsJul 19 2016The ability to backpropagate stochastic gradients through continuous latent distributions has been crucial to the emergence of variational autoencoders and stochastic gradient variational Bayes. The key ingredient is an unbiased and low-variance way of ... More
The probability of finding a fixed pattern in random data depends monotonically on the bifix indicatorJul 30 2012We consider the problem of finding a fixed L-ary sequence in a stream of random L-ary data. It is known that the expected search time is a strictly increasing function of the lengths of the bifices of the pattern. In this paper we prove the related statement ... More
The Local-Global Principle for Integral Soddy Sphere PackingsAug 27 2012Fix an integral Soddy sphere packing P. Let K be the set of all curvatures in P. A number n is called represented if n is in K, that is, if there is a sphere in P with curvature equal to n. A number n is called admissible if it is everywhere locally represented, ... More
Duality symmetry of BFKL equation: reggeized gluons vs color dipolesNov 27 2009We show that the duality symmetry of the BFKL equation can be interpreted as a symmetry under rotation of the BFKL Kernel in the transverse space from s-channel (color dipole model) to t-channel (reggeized gluon formulation). We argue that the duality ... More
Integer Lattice Gases at EquilibriumDec 14 2005Jan 24 2006Integer lattice gas automata can be utilized as building blocks in statistical mechanics. The presented deterministic and reversible automaton generates semiclassical statistical distributions. A possible approach to Bose-Einstein statistics from cellular ... More
Smooth models of singular $K3$-surfacesAug 24 2016Sep 05 2016We show that the classical Fermat quartic has exactly three smooth spatial models. As a generalization, we give a classification of smooth spatial (as well as some other) models of singular $K3$-surfaces of small discriminant. As a by-product, we observe ... More
On (Non)Supermodularity of Average Control EnergySep 27 2016Given a linear system, we consider the expected energy to move from the origin to a uniformly random point on the unit sphere as a function of the set of actuated variables. We show this function is not necessarily supermodular, correcting some claims ... More
A model-insensitive determination of First-hitting-time densities with Application to Equity default-swapsFeb 12 2010Mar 29 2010Equity default-swaps pay the holder a fixed amount of money when the underlying spot level touches a (far-down) barrier during the life of the instrument. While most pricing models give reasonable results when the barrier lies within the range of liquidly ... More
Critical phenomena in N=4 SYM plasmaMay 05 2010Strongly coupled N=4 supersymmetric Yang-Mills plasma at finite temperature and chemical potential for an R-symmetry charge undergoes a second order phase transition. We demonstrate that this phase transition is of the mean field theory type. We explicitly ... More
Gauge theories on hyperbolic spaces and dual wormhole instabilitiesFeb 21 2004Jul 26 2004We study supergravity duals of strongly coupled four dimensional gauge theories formulated on compact quotients of hyperbolic spaces. The resulting background geometries are represented by Euclidean wormholes, which complicates establishing the precise ... More
Compactifications of the N=2^* flowFeb 14 2003In hep-th/0004063 Pilch and Warner (PW) constructed N=2 supersymmetric RG flow corresponding to the mass deformation of the N=4 SU(N) Yang-Mills theory. In this paper we present exact deformations of PW flow when the gauge theory 3-space is compactified ... More
Finite temperature resolution of the Klebanov-Tseytlin singularityNov 16 2000Feb 19 2001Naked singularities in the gravitational backgrounds dual to gauge theories can be hidden behind the black hole horizon. We present an exact black hole solution in the Klebanov-Tseytlin geometry [hep-th/0002159]. Our solution realizes Maldacena dual of ... More
Violation of the holographic bulk viscosity boundOct 01 2011Motivated by gauge theory/string theory correspondence, a lower bound on the bulk viscosity of strongly coupled gauge theory plasma was proposed in arXiv:0708.3459. We consider strongly coupled N=4 supersymmetric Yang-Mills plasma compactified on a two-manifold ... More
Chiral symmetry breaking in cascading gauge theory plasmaDec 10 2010Nov 12 2013N=1 supersymmetric SU(K+P)xSU(K) cascading gauge theory of Klebanov et.al [1,2] undergoes a first-order finite temperature confinement/deconfinement phase transition at T_c=0.6141111(3) Lambda, where Lambda is the strong coupling scale of the theory. ... More
On universality of stress-energy tensor correlation functions in supergravityAug 11 2004Jan 21 2005Using the Minkowski space AdS/CFT prescription we explicitly compute in the low-energy limit the two-point correlation function of the boundary stress-energy tensor in a large class of type IIB supergravity backgrounds with a regular translationally invariant ... More
Gauge/string correspondence in curved spaceNov 15 2002Jan 08 2003We discuss Gubser-Klebanov-Polyakov proposal for the gauge/string theory correspondence for gauge theories in curved space. Specifically, we consider Klebanov-Tseytlin cascading gauge theory compactified on S^3. We explain regime when this gauge theory ... More
A Conical Tear Drop as a Vacuum-Energy Drain for the Solution of the Cosmological Constant ProblemJun 02 2004Feb 01 2005We propose a partial solution to the cosmological constant problem by using the simple observation that a three-brane in a six-dimensional bulk is flat. A model is presented in which Standard Model vacuum energy is always absorbed by the transverse space. ... More
Relativistic Superluminal NeutrinosSep 28 2011Oct 13 2011We present a possible solution to the reported OPERA anomaly for the speed of neutrinos, based on the idea that it is a local effect caused by a scalar field sourced by the earth. The coupling of the scalar to neutrinos effectively changes the background ... More
Universality of small black hole instability in AdS/CFTSep 25 2015$AdS_5$ type IIb supergravity compactifications on five-dimensional Einstein manifolds ${\cal V}_5$ realize holographic duals to four-dimensional conformal field theories. Black holes in such geometries are dual to thermal states in these CFTs. When black ... More
Eigenvalue Clustering, Control Energy, and Logarithmic CapacityNov 01 2015Apr 23 2016We prove two bounds showing that if the eigenvalues of a matrix are clustered in a region of the complex plane then the corresponding discrete-time linear system requires significant energy to control. A curious feature of one of our bounds is that the ... More
The "Most informative boolean function" conjecture holds for high noiseOct 29 2015We prove the "Most informative boolean function" conjecture of Courtade and Kumar for high noise $\epsilon \ge 1/2 - \delta$, for some absolute constant $\delta > 0$. Namely, if $X$ is uniformly distributed in $\{0,1\}^n$ and $Y$ is obtained by flipping ... More
The Debris Disk Fraction for M-dwarfs in Nearby, Young, Moving GroupsJan 25 2016I present the first substantial work to measure the fraction of debris disks for M-dwarfs in nearby moving groups (MGs). Utilising the $AllWISE$ IR catalog, 17 out of 151 MG members are found with an IR photometric excess indicative of disk structure. ... More
A Meta-Logic of Inference Rules: SyntaxNov 27 2014This work was intended to be an attempt to introduce the meta-language for working with multiple-conclusion inference rules that admit asserted propositions along with the rejected propositions. The presence of rejected propositions, and especially the ... More
Z(N) wall junctions: Monopole fossils in hot QCDFeb 27 2001We point out that the effective action of hot Yang--Mills theories has semi-classical solutions, which are naturally identified with monopole world lines, ``frozen'' into the short imaginary time dimension. The solutions look like wall junctions: lines ... More
n-Schur Functions and Determinants on an Infinite GrassmannianNov 11 1998A set of functions is defined which is indexed by a positive integer $n$ and partitions of integers. The case $n=1$ reproduces the standard Schur polynomials. These functions are seen to arise naturally as a determinant of an action on the frame bundle ... More
Description of Black Hole Microstates by Means of a Free Affine-Scalar FieldMay 13 2004In this article we will investigate the origin of central extensions in the Poisson algebra of charges, which arise in the dimensionally reduced theories describing black holes. We will see that the equations of motion and constraints arising from the ... More
Evolution of cooperation and communication skills as a consequence of environment fluctuationsSep 22 2006Dynamics of a social population is analyzed taking into account some physical constraints on individual behavior and decision making abilities. The model, based on Evolutionary Game Theory, predicts that a population has to pass through a series of different ... More
All-orders wormhole vertex operators from the Wheeler-deWitt equationJan 29 1992Jan 30 1992We discuss the calculation of semi-classical wormhole vertex operators from wave functions which satisfy the Wheeler-deWitt equation and momentum constraints, together with certain `wormhole boundary conditions'. We consider a massless minimally coupled ... More
The field of definition of affine invariant submanifolds of the moduli space of abelian differentialsOct 17 2012Apr 03 2014The field of definition of an affine invariant submanifold M is the smallest subfield of the reals such that M can be defined in local period coordinates by linear equations with coefficients in this field. We show that the field of definition is equal ... More
Sums of Adjoint OrbitsOct 09 2009Mar 26 2011Let G be a real compact connected simple Lie group, and g its Lie algebra. We study the problem of determining, from root data, when a sum of adjoint orbits in g, or a product of conjugacy classes in G, contains an open set. Our general methods allow ... More
The Tits Alternative: An Elementary ExpositionOct 09 2009Nov 25 2009This paper has been withdrawn by the author due to an error in the last paragraph of step 2 of the main proof, on page 6.
Josephson current noise above Tc in superconducting tunnel junctionsSep 11 2008Tunnel junction between two superconductors is considered in the vicinity of the critical temperature. Superconductive fluctuations above Tc give rise to the noise of the ac Josephson current although the current itself is zero in average. As a result ... More
Challenges and opportunities for applications of unconventional superconductorsAug 09 2013Since the discovery of high-$T_c$ cuprates the quest for new superconductors has shifted toward more anisotropic, strongly correlated materials with lower carrier densities and competing magnetic and charge density wave orders. While these materials features ... More
Central limit theorems via Stein's method for randomized experiments under interferenceApr 09 2018Controlling for interference through design and analysis can consume both engineering resources and statistical power, so it is of interest to understand the extent to which estimators and confidence intervals constructed under the SUTVA assumption are ... More
Odds of observing the multiverseDec 02 2008Jan 11 2010Eternal inflation predicts our observable universe lies within a bubble (or pocket universe) embedded in a volume of inflating space. The interior of the bubble undergoes inflation and standard cosmology, while the bubble walls expand outward and collide ... More
Complex interpolation of $Z$-spacesOct 25 2016We prove that the $Z$-spaces $Z^{p,q}_s$ form a complex interpolation scale for all $0 < p,q \leq \infty$ and $s \in \mathbb{R}$, filling a gap in recent work with Pascal Auscher.
Quantum tasks in holographyFeb 19 2019Jul 07 2019We consider an operational restatement of the holographic principle, which we call the principle of asymptotic quantum tasks. Asymptotic quantum tasks are quantum information processing tasks with inputs given and outputs required on points at the boundary ... More
Super-Replication of the Best Pairs Trade in HindsightOct 04 2018Mar 14 2019This paper derives a robust on-line equity trading algorithm that achieves the greatest possible percentage of the final wealth of the best pairs rebalancing rule in hindsight. A pairs rebalancing rule chooses some pair of stocks in the market and then ... More
Klebanov-Strassler black holeSep 22 2018Sep 26 2018We construct a black hole solution on warped deformed conifold in type IIB supergravity with fluxes. The black hole has translationary invariant horizon and is a holographic dual to a thermal homogeneous and isotropic state of a cascading $SU(K+P)\times ... More
Cosmology with extragalactic proper motions: harmonic formalism, estimators, and forecastsNov 13 2018Jun 13 2019We conduct a thorough study into the feasibility of measuring large-scale correlated proper motions of galaxies with astrometric surveys. We introduce a harmonic formalism for analysing proper motions and their correlation functions on the sphere based ... More
Gradable modules over artinian ringsAug 03 2018Let $\Lambda$ be a $\mathbb{Z}$-graded artin algebra. Two classical results of Gordon and Green state that if $\Lambda$ has only finitely many indecomposable gradable modules, up to isomorphism, then $\Lambda$ has finite representation type, and if $\Lambda$ ... More
Defending Malware Classification Networks Against Adversarial Perturbations with Non-Negative Weight RestrictionsJun 23 2018There is a growing body of literature showing that deep neural networks are vulnerable to adversarial input modification. Recently this work has been extended from image classification to malware classification over boolean features. In this paper we ... More
Tuning vortex fluctuations and the resistive transition in superconducting films with a thin overlayerJul 13 2018It is shown that the temperature of the resistive transition $T_r$ of a superconducting film can be increased by a thin superconducting or normal overlayer. For instance, deposition of a highly conductive thin overlayer onto a dirty superconducting film ... More
Quantum tasks in holographyFeb 19 2019May 23 2019We consider an operational restatement of the holographic principle, which we call the principle of asymptotic quantum tasks. Asymptotic quantum tasks are quantum information processing tasks with inputs given and outputs required on points at the boundary ... More
Tensor networks for dynamic spacetimesNov 18 2016May 19 2017Existing tensor network models of holography are limited to representing the geometry of constant time slices of static spacetimes. We study the possibility of describing the geometry of a dynamic spacetime using tensor networks. We find it is necessary ... More
How Einstein Discovered Dark EnergyNov 22 2012In 1917 Einstein published his Cosmological Considerations Concerning the General Theory of Relativity. In it was the first use of the cosmological constant. Shortly thereafter Schr\"odinger presented a note providing a solution to these same equations ... More
Long Run Feedback in the Broker Call Money MarketJun 24 2019I unravel the basic long run dynamics of the broker call money market, which is the pile of cash that funds margin loans to retail clients (read: continuous time Kelly gamblers). Call money is assumed to supply itself perfectly inelastically, and to continuously ... More
Compactifications and universal spaces in extension theoryAug 15 1999We show that for each countable simplicial complex P the following conditions are equivalent: (1) $P \in AE(X)$ iff $P \in AE(\beta X)$ for any space X; (2) There exists a P-invertible map of a metrizable compactum X with $P \in AE(X)$ onto the Hilbert ... More
Pseudocompact paratopological groupsMar 28 2010Sep 03 2013We obtain many results and solve some problems about pseudocompact paratopological groups. In particular, we obtain necessary and sufficient conditions when such a group is topological. (2-)pseudocompact paratopological groups that are not topological ... More
Complemented subspaces of products of Banach spacesFeb 28 2000We show that complemented subspaces of uncountable products of Banach spaces are products of complemented subspaces of countable subproducts.
On the Quantization of a Self-Dual Integrable SystemAug 24 2004In this note, we apply canonical quantization to the self-dual particle system describing the motion of poles to a higher rank solution of the KP hierarchy, explicitly determining both the quantum Hamiltonian and the wave function. It is verified that ... More
A generalization of Hagopian's theorem and exponentsMar 29 2000We generalize Hagopian's theorem characterizing solenoids to higher dimensions by showing that any homogeneous continuum admitting a fiber bundle projection onto a torus with totally disconnected fibers admits a compatible abelian topological group structure. ... More
Aspects of Classical Descriptive Set TheoryAug 28 2013This report consists of two parts. The first part is a brief exposition of classical descriptive set theory. This part introduces some fundamental concepts, motivations and results from the classical theory and ends with a section on the important result ... More
Fundamental groups of symmetric sexticsMar 21 2008Jul 13 2008We study the moduli spaces and compute the fundamental groups of plane sextics of torus type with at least two type $\bold{E}_6$ singular points. As a simple application, we compute the fundamental groups of 125 other sextics, most of which are new.
Stable symmetries of plane sexticsFeb 16 2008We classify projective symmetries of irreducible plane sextics with simple singularities which are stable under equivariant deformations. We also outline a connection between order~2 stable symmetries and maximal trigonal curves.
Irreducible plane sextics with large fundamental groupsDec 14 2007Sep 10 2008We compute the fundamental group of the complement of each irreducible sextic of weight eight or nine (in a sense, the largest groups for irreducible sextics), as well as of 169 of their derivatives (both of and not of torus type). We also give a detailed ... More
Oka's conjecture on irreducible plane sextics. IIFeb 19 2007We complete the proof of Oka's conjecture on the Alexander polynomial of an irreducible plane sextic. We also calculate the fundamental groups of irreducible sextics with a singular point adjacent to $J_{10}$.
On Popa's Cocycle Superrigidity TheoremAug 14 2006Sep 09 2006These notes contain an Ergodic-theoretic account of the Cocycle Superrigidity Theorem recently discovered by Sorin Popa. We state and prove a relative version of the result, discuss some applications to measurable equivalence relations, and point out ... More
The Negative Cycle Vectors of Signed Complete GraphsDec 30 2015Jun 29 2017A signed graph is a graph where the edges are assigned labels of either "$+$" or "$-$". The sign of a cycle in the graph is the product of the signs of its edges. We equip each signed complete graph with a vector whose entries are the number of negative ... More
Computer simulation of detecting system of compact positron-emission tomograph based on scintillator-photodiode detectorsMay 04 2017We present the original computer code for the simulation of multi-element detection system of the compact positron-emission tomograph based on a scintillator-photodiode type of detection elements. The use of such type of detection elements allows obtaining ... More
Cohomology monoids of monoids with coefficients in semimodules IIMar 27 2017We relate the old and new cohomology monoids of an arbitrary monoid $M$ with coefficients in semimodules over $M$, introduced in the author's previous papers, to monoid and group extensions. More precisely, the old and new second cohomology monoids describe ... More
Kahler: An Implementation of Discrete Exterior Calculus on Hermitian ManifoldsMay 30 2014Jun 04 2014This paper details the techniques and algorithms implemented in Kahler, a Python library that implements discrete exterior calculus on arbitrary Hermitian manifolds. Borrowing techniques and ideas first implemented in PyDEC, Kahler provides a uniquely ... More
Balanced Non-Transitive Dice II: TournamentsJun 27 2017We further study sets of labeled dice in which the relation "is a better die than" is non-transitive. Focusing on sets with an additional symmetry we call "balance," we prove that sets of $n$ such $m$-sided dice exist for all $n,m \geq 3$. We then show ... More
Topology of plane algebraic curves: the algebraic approachJul 02 2009We discuss the principle tools and results and state a few open problems concerning the classification and topology of plane sextics and trigonal curves in ruled surfaces.
On deformations of singular plane sexticsNov 15 2005Nov 27 2006We study complex plane projective sextic curves with simple singularities up to equisingular deformations. It is shown that two such curves are deformation equivalent if and only if the corresponding pairs are diffeomorphic. A way to enumerate all deformation ... More
Lines in supersingular quarticsApr 20 2016Jan 14 2019We show that the number of lines contained in a supersingular quartic surface is 40 or at most 32, if the characteristic of the field equals 2, and it is 112, 58, or at most 52, if the characteristic equals 3. If the quartic is not supersingular, the ... More
On Brauer-Kuroda type relations of S-class numbers in dihedral extensionsApr 16 2009Mar 03 2011Let F/k be a Galois extension of number fields with dihedral Galois group of order 2q, where q is an odd integer. We express a certain quotient of S-class numbers of intermediate fields, arising from Brauer-Kuroda relations, as a unit index. Our formula ... More
New Riemannian manifolds with $L^p$-unbounded Riesz transform for $p > 2$Jul 31 2017We construct a large class of Riemannian manifolds of arbitrary dimension with Riesz transform unbounded on $L^p(M)$ for all $p > 2$. This extends recent results for Vicsek manifolds, and in particular shows that fractal structure is not necessary for ... More
On plane sextics with double singular pointsJul 05 2012Jan 02 2013We compute the fundamental groups of five maximizing sextics with double singular points only; in four cases, the groups are as expected. The approach used would apply to other sextics as well, given their equations.
The Alexander module of a trigonal curveAug 15 2010Jul 24 2012We describe the Alexander modules and Alexander polynomials (both over $\Q$ and over finite fields $\FF{p}$) of generalized trigonal curves. The rational case is closed completely; in the case of characteristic $p>0$, a few points remain open.
Portfolio Optimization Under UncertaintyAug 11 2009Sep 21 2009Classical mean-variance portfolio theory tells us how to construct a portfolio of assets which has the greatest expected return for a given level of return volatility. Utility theory then allows an investor to choose the point along this efficient frontier ... More
Ł-Axiomatizability in intermediate and normal modal logicsJul 22 2014A set $F$ of formulas is complete relative to a given class of logics, if every logic from this class can be axiomatized by formulas from $F$. A set of formulas $F$ is {\L}-complete relative to a given class of logics, if every logic of this class can ... More
Sequence Transduction with Recurrent Neural NetworksNov 14 2012Many machine learning tasks can be expressed as the transformation---or \emph{transduction}---of input sequences into output sequences: speech recognition, machine translation, protein secondary structure prediction and text-to-speech to name but a few. ... More
Transition-Based Dependency Parsing With Pluggable ClassifiersNov 01 2012In principle, the design of transition-based dependency parsers makes it possible to experiment with any general-purpose classifier without other changes to the parsing algorithm. In practice, however, it often takes substantial software engineering to ... More
There are no noncommutative soft mapsFeb 02 2011It is shown that for a map $f \colon X \to Y$ of compact spaces the unital $\ast$-homomorphism $C(f) \colon C(Y) \to C(X)$ is projective in the category $\operatorname{Mor}({\mathcal C}^{1})$ precisely when $X$ is a dendrite and $f$ is either homeomorphism ... More
Effective Action of the Baryonic Branch in String Theory Flux ThroatsMay 07 2014Sep 12 2014We discuss consistent truncations of type IIB supergravity on resolved warped deformed conifolds with fluxes. These actions represent the gravitational duals to the baryonic branch deformation of the Klebanov-Strassler cascading gauge theory. As an application, ... More
On jet quenching parameters in strongly coupled non-conformal gauge theoriesMay 18 2006Aug 02 2006Recently Liu, Rajagopal and Wiedemann (LRW) [hep-ph/0605178] proposed a first principle, nonperturbative quantum field theoretic definition of ``jet quenching parameter'' \hat{q} used in models of medium-induced radiative parton energy loss in nucleus-nucleus ... More
Higher derivative corrections to near-extremal black holes in type IIB supergravityApr 24 2006Jun 08 2006We discuss string theory alpha' corrections to charged near-extremal black 3-branes/black holes in type IIB supergravity. We find that supersymmetric global AdS_5 x S^5 geometry is not corrected to leading order in alpha', while charged or non-extremal ... More
Inflation on the resolved warped deformed conifoldJan 01 2006Aug 10 2006Braneworld inflation on the resolved warped deformed conifold is represented by the dynamics of a D3-brane probe with the world volume of a brane spanning the large dimensions of the observable Universe. This model was recently proposed as a string theory ... More
Coarse-graining 1/2 BPS geometries of type IIB supergravitySep 26 2004Recently Lin, Lunin and Maldacena (LLM) (hep-th/0409174) explicitly mapped 1/2 BPS excitations of type IIB supergravity on AdS_5 x S^5 into free fermion configurations. We discuss thermal coarse-gaining of LLM geometries by explicitly mapping the corresponding ... More
Gauge/gravity correspondence in accelerating universeMar 06 2002Apr 16 2002We discuss time-dependent backgrounds of type IIB supergravity realizing gravitation duals of gauge theories formulated in de Sitter space-time as a tool of embedding de Sitter in a supergravity. We show that only the gravitational duals to non-conformal ... More
The Automorphisms group of \bar{M}_{g,n}Oct 07 2011Let \bar{\mathcal{M}}_{g,n}$ be the moduli stack parametrizing Deligne-Mumford stable n-pointed genus g curves and let \bar{M}_{g,n} be its coarse moduli space: the Deligne-Mumford compactification of the moduli space of n-pointed genus g smooth curves. ... More
Linear Time Average Consensus on Fixed Graphs and Implications for Decentralized Optimization and Multi-Agent ControlNov 15 2014May 23 2016We describe a protocol for the average consensus problem on any fixed undirected graph whose convergence time scales linearly in the total number nodes $n$. The protocol is completely distributed, with the exception of requiring all nodes to know the ... More
Magnetization suppression of Type-II Superconductors by external alternating magnetic fieldDec 27 2004The effect of suppression of static magnetization of an anisotropic hard superconductor by alternating magnetic field is analyzed theoretically. The magnetic moment suppression dynamics is described with respect to the magnetization loop of the superconductor. ... More
Recent Results From CLEO-cMay 23 2005This paper describes recent preliminary results from the CLEO-c experiment using an initial ~60 pb^-1 sample of data collected in e^+e^- collisions at a center of mass energy around the mass of the psi(3770). A first measurement of the branching fraction ... More
Orbit equivalence rigidityNov 01 1999Consider a countable group Gamma acting ergodically by measure preserving transformations on a probability space (X,mu), and let R_Gamma be the corresponding orbit equivalence relation on X. The following rigidity phenomenon is shown: there exist group ... More
A multivariate CLT in Wasserstein distance with near optimal convergence rateFeb 17 2016Let $X_1, \ldots , X_n$ be i.i.d. random vectors in $\mathbb{R}^d$ with $\|X_1\| \le \beta$. Then, we show that $\frac{1}{\sqrt{n}}(X_1 + \ldots + X_n)$ converges to a Gaussian in Wasserstein-2 distance at a rate of $O\left(\frac{\sqrt{d} \beta \log n}{\sqrt{n}} ... More
Long-time existence for Yang-Mills flowOct 11 2016Nov 09 2016We establish that finite-time singularities do not occur in four-dimensional Yang-Mills flow, confirming the conjecture of Schlatter, Struwe, and Tahvildar-Zadeh. The proof relies on a weighted energy identity and sharp decay estimates in the neck region. ... More