Results for "Amit Agarwal"

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Power dissipation for systems with junctions of multiple quantum wiresJul 29 2009Jan 16 2010We study power dissipation for systems of multiple quantum wires meeting at a junction, in terms of a current splitting matrix (M) describing the junction. We present a unified framework for studying dissipation for wires with either interacting electrons ... More
Negative longitudinal magnetoresistance in the density wave phase of Y$_2$Ir$_2$O$_7$Feb 08 2018The ground state of nanowires of single crystalline Pyrochlore Y$_2$Ir$_2$O$_7$ is a density wave. Application of a {\it transverse} magnetic field increases the threshold electric field for the collective de-pinning of the density wave state at low temperature, ... More
Amplification of NOON StatesDec 28 2009We examine the behavior of a Non Gaussian state like NOON state under phase insensitive amplification. We derive analytical result for the density matrix of the NOON state for arbitrary gain of the amplifier. We consider cases of both symmetric and antisymmetric ... More
Time resolved transport properties of a $Y$-junction of Tomonaga-Luttinger liquidsJun 30 2014Nov 05 2014We study time resolved transport properties of a $Y$-junction composed of interacting one-dimensional quantum wires using a bosonization approach. In particular, we investigate the AC conductivity of the $Y$-junction formed from finite length Tomonaga-Luttinger ... More
Four allotropes of semiconducting layered Arsenic which switch into a topological insulator via an electric field: A computational studyApr 11 2016Jun 29 2016We propose four different thermodynamically stable structural phases of arsenic monolayers based on ab-initio density functional theory calculations all of which undergo a topological phase transition on application of a perpendicular electric field. ... More
Line junction in a quantum Hall system with two filling fractionsMar 10 2008We present a microscopic model for a line junction formed by counter or co-propagating single mode quantum Hall edges corresponding to different filling factors. The ends of the line junction can be described by two possible current splitting matrices ... More
Charge transport in a Tomonaga-Luttinger liquid: effects of pumping and biasFeb 19 2007Jul 07 2007We study the current produced in a Tomonaga-Luttinger liquid by an applied bias and by weak, point-like impurity potentials which are oscillating in time. We use bosonization to perturbatively calculate the current up to second order in the impurity potentials. ... More
Enhancement of tunneling density of states at a Y junction of spin-1/2 Tomonaga Luttinger liquid wiresFeb 10 2015Jul 21 2015We calculate the tunneling density of states (TDOS) in a three wire junction of interacting spin-1/2 electrons, and find an anomalous enhancement of the TDOS in the zero bias limit, even for repulsive interactions for several bosonic fixed points. This ... More
Equation of motion approach to non-adiabatic quantum charge pumpingMar 22 2006Jan 18 2007We use the equations of motion of non-interacting electrons in a one-dimensional system to numerically study different aspects of charge pumping. We study the effects of the pumping frequency, amplitude, band filling and finite bias on the charge pumped ... More
Plasmons in spin polarized graphene: a new way to measure spin polarizationMay 05 2015Jun 14 2015We study the collective charge excitations (plasmons) in spin polarized graphene, and derive explicit expressions for their dispersion in the undamped regime. From this, we are able to calculate the critical wave vector beyond which the plasmon enters ... More
AC conductivity of a quantum Hall line junctionSep 08 2008Aug 14 2009We present a microscopic model for calculating the AC conductivity of a finite length line junction made up of two counter or co-propagating single mode quantum Hall edges with possibly different filling fractions. The effect of density-density interactions ... More
Conductance of quantum wires: a numerical study of the effects of an impurity and interactionsJul 05 2005Mar 02 2006We use the non-equilibrium Green's function formalism along with a self-consistent Hartree-Fock approximation to numerically study the effects of a single impurity and interactions between the electrons (with and without spin) on the conductance of a ... More
Nonadiabatic charge pumping in a one-dimensional system of noninteracting electrons by an oscillating potentialAug 27 2007Dec 24 2007Using a tight-binding model, we study one-parameter charge pumping in a one-dimensional system of non-interacting electrons. An oscillating potential is applied at one site while a static potential is applied in a different region. Using Floquet scattering ... More
Thickness and electric field dependent polarizability and dielectric constant in phosphoreneFeb 29 2016Mar 23 2016Based on extensive first principle calculations, we explore the thickness dependent effective di- electric constant and slab polarizability of few layer black phosphorene. We find that the dielectric constant in ultra-thin phosphorene is thickness dependent ... More
Effective Doping of Monolayer Phosphorene by Surface Adsorption of Atoms for Electronic and Spintronic ApplicationsMar 14 2015Aug 07 2015We study the effect of surface adsorption of 27 different adatoms on the electronic and magnetic properties of monolayer black phosphorus using density functional theory. Choosing a few representative elements from each group, ranging from alkali metals ... More
Efficient Optimal Algorithm of Task Scheduling in Cloud Computing EnvironmentApr 08 2014Cloud computing is an emerging technology in distributed computing which facilitates pay per model as per user demand and requirement.Cloud consist of a collection of virtual machine which includes both computational and storage facility. The primary ... More
Possibility of Coherent Phenomena like Bloch Oscillations with Single Photons via W-StatesFeb 09 2009Nov 30 2009We examine the behavior of single photons at multiport devices and inquire if coherent effects are possible. In particular we study how single photons need to be manipulated in order to study coherent phenomena. We show that single photons need to be ... More
A Quantum Optical SpringJan 24 2008We study the dynamics of the quantum optical spring, i.e., a spring whose spring constant undergoes discreet jumps depending on the quantum state of another system. We show the existence of revivals and fractional revivals in the quantum dynamics reminiscent ... More
Dynamical polarizability, screening, and plasmons in one, two, and three dimensional massive Dirac systemsApr 04 2016Nov 10 2016We study the density-density response function of a collection of charged massive Dirac particles and present analytical expressions for the dynamical polarization function in one, two and three dimensions. The polarization function is then used to find ... More
Finite time interaction quench in a Luttinger modelNov 08 2013Jun 28 2014We analyze the dynamics of a Luttinger model following a quench in the electron-electron interaction strength, where the change in the interaction strength occurs over a finite time scale $\tau$. We study the Loschmidt echo (the overlap between the initial ... More
Casimir effect for a Bose-Einstein condensate inside a cylindrical tubeAug 25 2014Nov 08 2015We explore Casimir effect on an interacting Bose-Einstein condensate (BEC) inside a cylindrical tube. The Casimir force for the confined BEC comprises of (i) a mean-field part arising from the spatial inhomogeneity of the condensate order parameter, and ... More
Dynamical polarizability, screening, and plasmons in one, two, and three dimensional massive Dirac systemsApr 04 2016We study the density-density response function of a collection of charged massive Dirac particles and present analytical expressions for the dynamical polarization function in one, two and three dimensions. The polarization function is then used to find ... More
Impact of Underlaid Multi-antenna D2D on Cellular Downlink in Massive MIMO SystemsNov 03 2015Mar 30 2016In this paper, we consider a massive multiple-input multiple-output (MIMO) downlink system underlaid with a network of multi-antenna D2D user equipments (UEs). Each D2D transmitter (Tx) uses all its antennas to beamform information towards its desired ... More
Anisotropic transport of normal metal-barrier-normal metal junctions in monolayer phosphoreneOct 07 2016We study transport properties of a phosphorene monolayer in the presence of single and multiple potential barriers of height $U_0$ and width $d$, using both continuum and microscopic lattice models, and show that the nature of electron transport along ... More
Non-Gaussian and Gaussian Entanglement in Coupled Leaky WaveguidesJul 14 2009Mar 07 2013We investigate the viability of coupled waveguides as basic units of quantum circuits. In particular, we study the dynamics of entanglement for the single photon state, and single mode squeezed vacuum state. We further consider the case of entangled inputs ... More
Toward a Push-Scalable Global InternetNov 29 2010Push message delivery, where a client maintains an ``always-on'' connection with a server in order to be notified of a (asynchronous) message arrival in real-time, is increasingly being used in Internet services. The key message in this paper is that ... More
Mass Deformations of Super Yang-Mills Theories in D= 2+1, and Super-Membranes: A NoteJun 26 2008Mass deformations of supersymmetric Yang-Mills theories in three spacetime dimensions are considered. The gluons of the theories are made massive by the inclusion of a non-local gauge and Poincare invariant mass term due to Alexanian and Nair, while the ... More
Open Spin Chains in Super Yang-Mills at Higher Loops: Some Potential Problems with IntegrabilityMar 09 2006May 14 2006The super Yang-Mills duals of open strings attached to maximal giant gravitons are studied in perturbation theory. It is shown that non-BPS baryonic excitations of the gauge theory can be studied within the paradigm of open quantum spin chains even beyond ... More
In-plane hole density in Ca(0.1)La(0.9)Ba(1.65)La(0.35)Cu(3)O(y) ; nuclear resonance study over the full doping rangeJun 18 2006We report in-plane Cu(63) Nuclear Magnetic Resonance measurements for a series of fully enriched Ca(0.1)La(0.9)Ba(1.65)La(0.35)Cu(3)O(y) powder samples, which belong to the YBCO family, but the doping could vary from very underdoped to extremely overdoped. ... More
Strings in a 2-d Extremal Black HoleDec 24 2004Jan 05 2005String theory on 2-d charged black holes corresponding to (SL(2)xU(1)_L)/U(1) exact asymmetric quotient CFTs are investigated. These backgrounds can be embedded, in particular, in a two dimensional heterotic string. In the extremal case, the quotient ... More
Aspects of Integrability in N =4 SYMAug 21 2007Various recently developed connections between supersymmetric Yang-Mills theories in four dimensions and two dimensional integrable systems serve as crucial ingredients in improving our understanding of the AdS/CFT correspondence. In this review, we highlight ... More
Mass-Gaps and Spin Chains for (Super) MembranesOct 01 2006We present a method for computing the non-perturbative mass-gap in the theory of Bosonic membranes in flat background spacetimes with or without background fluxes. The computation of mass-gaps is carried out using a matrix regularization of the membrane ... More
On Computation of Error Locations and Values in Hermitian CodesDec 11 2007We obtain a technique to reduce the computational complexity associated with decoding of Hermitian codes. In particular, we propose a method to compute the error locations and values using an uni-variate error locator and an uni-variate error evaluator ... More
A Supersymmetry Preserving Mass-Deformation of N=1 Super Yang-Mills in D=2+1Sep 04 2009Sep 18 2009We construct a massive non-abelian N= 1 SYM theory on R^3. This is achieved by using a non-local gauge and Poincare invariant mass term for gluons due to Nair. The underlying supersymmetry algebra is shown to be a non-central extension of the Poincare ... More
Towards a PURE Spoken Dialogue System for Information AccessJul 22 1997With the rapid explosion of the World Wide Web, it is becoming increasingly possible to easily acquire a wide variety of information such as flight schedules, yellow pages, used car prices, current stock prices, entertainment event schedules, account ... More
Comments on Higher Loop Integrability in the $su(1|1)$ Sector of $\cal N$=4 $SYM$: Lessons From the $su(2)$ SectorJun 13 2005An analysis of two loop integrability in the $su(1|1)$ sector of $\cal{N}$=4$SYM$ is presented from the point of view of Yangian symmetries. The analysis is carried out in the scaling limit of the dilatation operator which is shown to have a manifest ... More
Surrogate Regret Bounds for Bipartite Ranking via Strongly Proper LossesJul 02 2012The problem of bipartite ranking, where instances are labeled positive or negative and the goal is to learn a scoring function that minimizes the probability of mis-ranking a pair of positive and negative instances (or equivalently, that maximizes the ... More
A Novel MINLP Reformulation for Nonlinear Generalized Disjunctive Programming (GDP) ProblemsOct 07 2015In optimization problems, often equations and inequalities are represented using if-else (implication) construct which is known to be equivalent to a disjunction. Such statements are modeled and incorporated in an optimization problem using Generalized ... More
Wave packet dynamics in various two-dimensional systems: a unified descriptionOct 14 2014In this article we present an exact and unified description of wave-packet dynamics in various 2D systems in presence of a transverse magnetic field. We consider an initial minimum-uncertainty Gaussian wave-packet, and find that its long term dynamics ... More
Wave packet dynamics in monolayer MoS$_2$ with and without a magnetic fieldApr 17 2014May 01 2014We study the dynamics of electrons in monolayer Molybdenum Disulfide (MoS$_2$), in the absence as well as presence of a transverse magnetic field. Considering the initial electronic wave function to be a Gaussian wave packet, we calculate the time dependent ... More
Electric-field tunable Dirac semimetal state in phosphorene thin filmsSep 12 2016Nov 10 2016We study the electric-field tunable electronic properties of phosphorene thin films, using the framework of density functional theory. We show that phosphorene thin films offer a versatile material platform to study two dimensional Dirac fermions on application ... More
New ground states of fluorinated and oxidized phosphorene: structural and electronic propertiesJul 26 2015Mar 24 2016We systematically explore chemical functionalization of monolayer black phosphorene via chemisorption of oxygen and fluorine atoms. Using the cluster expansion technique, with vary- ing concentration of the adsorbate, we determine the ground states considering ... More
Transport and Quantum Walk of Nonclassical Light in Coupled WaveguidesJul 19 2008We study the transport and quantum walk of nonclassical light in an array of coupled waveguides which have novel properties like very low decoherence and thus making them ideal for storage of quantum information. We show how squeezing gets turned over ... More
Electric-field tunable Dirac semimetal state in phosphorene thin filmsSep 12 2016We study the electric-field tunable electronic properties of phosphorene thin films, using the framework of density functional theory. We show that phosphorene thin films offer a versatile material platform to study two dimensional Dirac fermions on application ... More
Plasmon modes of a massive Dirac plasma, and their superlatticesFeb 26 2015May 20 2015We explore the collective density oscillations of a collection of charged massive Dirac particles, in one, two and three dimensions and their one dimensional superlattice. We calculate the long wavelength limit of the dynamical polarization function analytically, ... More
Enhancement of tunneling density of states at a junction of three Luttinger liquid wiresOct 20 2008Jul 31 2009We study the tunneling density of states (TDOS) for a junction of three Tomonaga-Luttinger liquid wires. We show that there are fixed points which allow for the enhancement of the TDOS, which is unusual for Luttinger liquids. The distance from the junction ... More
Long-lived spin plasmons in a spin-polarized two-dimensional electron gasJun 04 2014Oct 10 2014Collective charge-density modes (plasmons) of the clean two-dimensional unpolarized electron gas are stable, for momentum conservation prevents them from decaying into single-particle excitations. Collective spin-density modes (spin plasmons) possess ... More
Persistent spin oscillations in a spin-orbit-coupled superconductorMay 23 2011Aug 17 2011Quasi-two-dimensional superconductors with tunable spin-orbit coupling are very interesting systems with properties that are also potentially useful for applications. In this manuscript we demonstrate that these systems exhibit undamped collective spin ... More
Electric field induced gap modification in ultrathin blue phosphorousDec 02 2014Mar 18 2015We investigate the possibility of band structure engineering in the recently predicted 2D layered form of blue phosphorus via an electric field (E$_z$) applied perpendicular to the layer(s). Using density functional theory, we study the effect of a transverse ... More
A Few Ways to Destroy Entropic Chaoticity on Kac's SphereAug 31 2012In this work we discuss a few ways to create chaotic families that are not entropically chaotic on Kac's Sphere. We present two types of examples: limiting convex combination of an entropically chaotic family with a particularly 'bad' non-entropic family, ... More
A note on uniform intersecting families with maximum transversal sizeSep 16 2014We construct an intersecting $k$-family of transversal size $\lceil \frac{k+1}{2} \rceil$ and length $k+1$ and study some of its properties. We use this family to prove that $q(4) = 9$. We also construct a $k$-family for $k = 2^m - 1$ of length $2k+1$ ... More
Hecke-Bochner identity and eigenfunctions associated to Gelfand pairs on the Heisenberg groupJun 12 2012Let $\mathbb{H}^{n}$ be the $(2n+1)$-dimensional Heisenberg group, and let $K$ be a compact subgroup of U(n), such that $(K,\mathbb{H}^{n})$ is a Gelfand pair. Also assume that the $K$-action on $\mathbb{C}^n$ is polar. We prove a Hecke-Bochner identity ... More
Rank 3 arithmetically Cohen-Macaulay bundles on hypersurfacesJun 10 2015Let $X$ be a smooth projective hypersurface of dimension $\geq 5$ and let $E$ be an arithmetically Cohen-Macaulay bundle on $X$ of any rank. We prove that $E$ splits as a direct sum of line bundles if and only if $H^i_*(X, \wedge^2 E) = 0$ for $i = 1,2,3,4$. ... More
Rotational Doppler EffectAug 08 2002A monochromatic linear source of light is rotated with certain angular frequency and when such light is analysed after reflection then a change of frequency or wavelength may be observed depending on the location of the observer. This change of frequency ... More
Six generated ACM bundles on a hypersurfaceJul 29 2014Let X be a smooth projective hypersurface. In this note we show that any six generated arithmetically Cohen-Macaulay vector bundle over X splits if dim X >= 6.
The Brauer Group of a Smooth OrbifoldNov 05 2008Let $k$ be a field and $X/k$ be a smooth quasiprojective orbifold. Let $X\to \underline{X}$ be its coarse moduli space. In this paper we study the Brauer group of $X$ and compare it with the Brauer group of the smooth locus of $\underline{X}$.
A manifold of possible physics-laws in a universe where the planck constant and speed of light parameters varyFeb 14 2008I assume a universe whereby the speed of light and the planck constant are not constants but instead parameters that vary locally in time-and space. When describing motion, I am able to derive a modified path integral description at the quantum level, ... More
Evidence of magnetic mechanism for cuprate superconductivitySep 05 2009A proper understanding of the mechanism for cuprate superconductivity can emerge only by comparing materials in which physical parameters vary one at a time. Here we present a variety of bulk, resonance, and scattering measurements on the (Ca_xLa_{1-x})(Ba_{1.75-x}La_{0.25+x})Cu_3O_y ... More
Radically filtered quasi-hereditary algebras and rigidity of tilting modulesJan 28 2015Jun 08 2015Let $A$ be a quasi-hereditary algebra. We prove that in many cases, a tilting module is rigid (i.e. has identical radical and socle series) if it does not have certain subquotients whose composition factors extend more than one layer in the radical series ... More
Dual conformal transformations of smooth holographic Wilson loopsOct 23 2016We study dual conformal transformations of minimal area surfaces in $AdS_5 \times S^5$ corresponding to holographic smooth Wilson loops and some other related observables. To act with dual conformal transformations we map the string solutions to the dual ... More
The Resultant of an Unmixed Bivariate SystemSep 11 2002This paper gives an explicit method for computing the resultant of any sparse unmixed bivariate system with given support. We construct square matrices whose determinant is exactly the resultant. The matrices constructed are of hybrid Sylvester and B\'ezout ... More
On the homotopy theory of $\mathbf{G}$ - spacesDec 11 2015The aim of this paper is to show that the most elementary homotopy theory of $\mathbf{G}$-spaces is equivalent to a homotopy theory of simplicial sets over $\mathbf{BG}$, where $\mathbf{G}$ is a fixed group. Both homotopy theories are presented as Relative ... More
A Survey on BGP Issues and SolutionsJul 28 2009BGP is the de facto protocol used for inter-autonomous system routing in the Internet. Generally speaking, BGP has been proven to be secure, efficient, scalable, and robust. However, with the rapid evolving of the Internet in the past few decades, there ... More
A Counter Example to Cercignani's Conjecture for the $d$ Dimensional Kac ModelApr 26 2012Kac's $d$ dimensional model gives a linear, many particle, binary collision model from which, under suitable conditions, the celebrated Boltzmann equation, in its spatially homogeneous form, arise as a mean field limit. The ergodicity of the evolution ... More
Grothendieck Rings of Theories of ModulesFeb 18 2013The model-theoretic Grothendieck ring of a first order structure, as defined by Krajic\v{e}k and Scanlon, captures some combinatorial properties of the definable subsets of finite powers of the structure. In this paper we compute the Grothendieck ring, ... More
On the Subadditivity of the Entropy on the SphereApr 05 2014Apr 01 2015We present a refinement of a known entropic inequality on the sphere, finding suitable conditions under which the uniform probability measure on the sphere behaves asymptomatically like the Gaussian measure on $\mathbb{R}^N$ with respect to the entropy. ... More
Alternative method of generation of Cerenkov radiation or shock waveSep 02 1997An alternative method of generation of Cerenkev radiation is proposed over here with the help of a rotating source and a reflector. The principle is that, if we focus a narrow beam of light on to source of light is rotated with certain angular velocity ... More
Splitting of low rank ACM bundles on hypersurfaces of high dimensionApr 08 2013Feb 02 2015Let $X$ be a smooth projective hypersurface. In this note we show that any rank 3 arithmetically Cohen-Macaulay vector bundle over $X$ splits when dim $X \geq 7$. We also find a splitting criterion for rank 4 arithmetically Cohen-Macaulay vector bundles ... More
Duality as a Gauge Symmetry and Topology ChangeOct 04 1993Duality groups as (spontaneously broken) gauge symmetries for toroidal backgrounds, and their role in ($\infty$-dimensional) underlying string gauge algebras are reviewed. For curved backgrounds, it is shown that there is a duality in the moduli space ... More
Anisotropy-Induced Quantum Interference Between Orthogonal Quantum Dot Exciton States in Semiconductor Cavity SystemsAug 23 2016We describe how quantum dot semiconductor cavity systems can be engineered to exploit anisotropy-induced dipole-dipole coupling between orthogonal dipole states in a single quantum dot. Quantum dots in single-mode cavity structures with spin exciton states, ... More
Manifest SO(N) invariance and S-matrices of three-dimensional N=2,4,8 SYMMar 03 2011An on-shell formalism for the computation of S-matrices of SYM theories in three spacetime dimensions is presented. The framework is a generalization of the spinor-helicity formalism in four dimensions. The formalism is applied to establish the manifest ... More
Deconstructing Supersymmetric S-matrices in D <= 2 + 1Jun 08 2012Global supersymmetries of the S-matrices of N = 2, 4, 8 supersymmetric Yang-Mills theories in three spacetime dimensions (without matter hypermultiplets) are shown to be SU(1|1), SU(2|2) and SU(2|2) X SU(2|2) respectively. These symmetries are not manifest ... More
Hidden Local and Non-local Symmetries of S-matrices of N=2,4,8 SYM in D=2+1Sep 13 2011Sep 26 2011This talk, based principally on arXiv:1103.0786, is devoted to properties of tree-level S-matrices of N=2,4,8 SYM in D=2+1. We'll discuss an on-shell formalism for three-dimensional theories inspired by the spinor-helicity framework in four spacetime ... More
Power and efficiency analysis of a realistic resonant tunneling diode thermoelectricMar 04 2014Jul 01 2014Low-dimensional systems with sharp features in the density of states have been proposed as a means to improving the efficiency of thermoelectric devices. Quantum dot systems, which offer the sharpest density of states achievable, however, suffer from ... More
Local Partial Clique Covers for Index CodingMar 08 2016Apr 29 2016Index coding, or broadcasting with side information, is a network coding problem of most fundamental importance. In this problem, given a directed graph, each vertex represents a user with a need of information, and the neighborhood of each vertex represents ... More
Supersymmetric Wilson Loops in Diverse DimensionsApr 03 2009Aug 12 2009We consider supersymmetric Wilson loops a la Zarembo in planar supersymmetric Yang-Mills theories in diverse dimensions. Using perturbation theory we show that these loops have trivial vacuum expectation values to second order in the 't Hooft coupling. ... More
Spider and the Flies : Focused Crawling on Tumblr to Detect Hate Promoting CommunitiesMar 30 2016Tumblr is one of the largest and most popular microblogging website on the Internet. Studies shows that due to high reachability among viewers, low publication barriers and social networking connectivity, microblogging websites are being misused as a ... More
A Relevant Content Filtering Based Framework For Data Stream SummarizationJun 23 2016Social media platforms are a rich source of information these days, however, of all the available information, only a small fraction is of users' interest. To help users catch up with the latest topics of their interests from the large amount of information ... More
Adaptive Resolution Simulation in Equilibrium and BeyondDec 07 2014In this paper, we investigate the equilibrium statistical properties of both the force and potential interpolations of adaptive resolution simulation (AdResS) under the theoretical framework of grand-canonical like AdResS (GC-AdResS). The thermodynamic ... More
Bounds on the Rate of Linear Locally Repairable Codes over Small AlphabetsJul 28 2016Locally repairable codes (LRC) have recently been a subject of intense research due to theoretical appeal and their application in distributed storage systems. In an LRC, any coordinate of a codeword can be recovered by accessing only few other coordinates. ... More
Security in Locally Repairable StorageMar 13 2015Aug 12 2016In this paper we extend the notion of {\em locally repairable} codes to {\em secret sharing} schemes. The main problem that we consider is to find optimal ways to distribute shares of a secret among a set of storage-nodes (participants) such that the ... More
Continuous Optimization for Fields of Experts Denoising WorksMar 21 2014Several recent papers use image denoising with a Fields of Experts prior to benchmark discrete optimization methods. We show that a non-linear least squares solver significantly outperforms all known discrete methods on this problem.
Multiple Signal Classification Algorithm (MUSICAL) for super-resolution fluorescence microscopyNov 28 2016Super-resolution microscopy is providing unprecedented insights into biology by resolving details much below the diffraction limit. State-of-the-art Single Molecule Localization Microscopy (SMLM) techniques for super-resolution are restricted by long ... More
A Lower Bound for the Optimization of Finite SumsOct 02 2014Oct 04 2015This paper presents a lower bound for optimizing a finite sum of $n$ functions, where each function is $L$-smooth and the sum is $\mu$-strongly convex. We show that no algorithm can reach an error $\epsilon$ in minimizing all functions from this class ... More
Thermal Tachyacoustic CosmologyJun 03 2014An intriguing possibility that can address pathologies in both early universe cosmology (i.e. the horizon problem) and quantum gravity (i.e. non-renormalizability), is that particles at very high energies and/or temperatures could propagate arbitrarily ... More
Pronounced Effect of pn-Junction Dimensionality on Tunnel Switch Threshold ShapeSep 01 2011Oct 30 2014Designing tunneling junctions with abrupt on-off characteristics and high current densities is critical for many different devices including backward diodes and tunneling field effect transistors (TFETs). It is possible to get a sharp, high conductance ... More
Portfolio Benchmarking under Drawdown Constraint and Stochastic Sharpe RatioOct 26 2016We consider an investor who seeks to maximize her expected utility derived from her terminal wealth relative to the maximum performance achieved over a fixed time horizon, and under a portfolio drawdown constraint, in a market with local stochastic volatility ... More
Gauge Theories on Open Lie Algebra Non-Commutative SpacesNov 13 2002Nov 26 2002It is shown that non-commutative spaces, which are quotients of associative algebras by ideals generated by non-linear relations of a particular type, admit extremely simple formulae for deformed or star products. Explicit construction of these star products ... More
Energy Aware, Scalable, K-Hop Based Cluster Formation In MANETSep 21 2012The study of Mobile Ad-hoc Network remains attractive due to the desire to achieve better performance and scalability. MANETs are distributed systems consisting of mobile hosts that are connected by multi-hop wireless links. Such systems are self organized ... More
Fine-Grained Complexity and Conditional Hardness for Sparse GraphsNov 21 2016There is a large class of path and cycle problems on graphs that currently have $\tilde{O}(n^3)$ time algorithms. Graphs encountered in practice are typically sparse, with $m <<n^2$, were $n$ and $m$ are the number of vertices and edges in the graph. ... More
On some new inequalities involving generalized Erdélyi-Kober fractional $q$-integral operatorMay 27 2014In the present investigation, we aim to establish some inequalities involving generalized Erd\'elyi-Kober fractional $q$-integral operator of the two parameters of deformation $q_{1}$ and $q_{2}$ due to Gaulu\'e, by following the same lines used by Baleanu ... More
Finding $k$ Simple Shortest Paths and CyclesDec 07 2015Feb 23 2016The problem of finding multiple simple shortest paths in a weighted directed graph $G=(V,E)$ has many applications, and is considerably more difficult than the corresponding problem when cycles are allowed in the paths. Even for a single source-sink pair, ... More
Higher Charges in Dynamical Spin Chains for SYM TheoryAug 19 2005Aug 30 2005We construct, to the first two non-trivial orders, the next conserved charge in the su(2|3) sector of N=4 Super Yang-Mills theory. This represents a test of integrability in a sector where the interactions change the number of sites of the chain. The ... More
Role of Heterogeneities in Staebler-Wronski EffectSep 12 2012The effect of light soaking (LS) on the properties of hydrogenated amorphous silicon presents many challenging puzzles. Some of them are discussed here, along with their present status. In particular the role of the heterogeneities in LS is examined. ... More
Support Vector Algorithms for Optimizing the Partial Area Under the ROC CurveMay 13 2016The area under the ROC curve (AUC) is a widely used performance measure in machine learning. Increasingly, however, in several applications, ranging from ranking to biometric screening to medicine, performance is measured not in terms of the full area ... More
Applying Social Media Intelligence for Predicting and Identifying On-line Radicalization and Civil Unrest Oriented ThreatsNov 21 2015Research shows that various social media platforms on Internet such as Twitter, Tumblr (micro-blogging websites), Facebook (a popular social networking website), YouTube (largest video sharing and hosting website), Blogs and discussion forums are being ... More
The dynamical viability of scalar-tensor gravity theoriesAug 29 2007Jun 23 2008We establish the dynamical attractor behavior in scalar-tensor theories of dark energy, providing a powerful framework to analyze classes of theories, predicting common evolutionary characteristics that can be compared against cosmological constraints. ... More
Anisotropic Vacuum Induced Interference in Decay ChannelsMay 23 2000We demonstrate how the anisotropy of the vacuum of the electromagnetic field can lead to quantum interferences among the decay channels of close lying states. Our key result is that interferences are given by the {\em scalar} formed from the antinormally ... More
Beyond the Singularity of the 2-D Charged Black HoleMay 16 2003Jul 23 2003Two dimensional charged black holes in string theory can be obtained as exact (SL(2,R)xU(1))/U(1) quotient CFTs. The geometry of the quotient is induced from that of the group, and in particular includes regions beyond the black hole singularities. Moreover, ... More
Nonlinear optical conductivity of a generic two band systems, with application to doped and gapped grapheneJun 16 2016We present a general formulation to calculate the dynamic optical conductivity, beyond the linear response regime, of any electronic system whose quasiparticle dispersion is described by a two band model. Our phenomenological model is based on the optical ... More