Results for "Nikhil Mehta"

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Improving Natural Language Interaction with Robots Using AdviceMay 12 2019Over the last few years, there has been growing interest in learning models for physically grounded language understanding tasks, such as the popular blocks world domain. These works typically view this problem as a single-step process, in which a human ... More
Stochastic Blockmodels meet Graph Neural NetworksMay 14 2019Stochastic blockmodels (SBM) and their variants, $e.g.$, mixed-membership and overlapping stochastic blockmodels, are latent variable based generative models for graphs. They have proven to be successful for various tasks, such as discovering the community ... More
Robust and Fast 3D Scan Alignment using Mutual InformationSep 20 2017This paper presents a mutual information (MI) based algorithm for the estimation of full 6-degree-of-freedom (DOF) rigid body transformation between two overlapping point clouds. We first divide the scene into a 3D voxel grid and define simple to compute ... More
On Equal Point Separation by Planar Cell DecompositionsJan 17 2017In this paper, we investigate the problem of separating a set $X$ of points in $\mathbb{R}^{2}$ with an arrangement of $K$ lines such that each cell contains an asymptotically equal number of points (up to a constant ratio). We consider a property of ... More
Multi-Band Feeds: A Design StudyOct 11 2012Broadband antenna feeds are of particular interest to existing and future radio telescopes for multi-frequency studies of astronomical sources. Although a 1:15 range in frequency is difficult to achieve, the well-known Eleven feed design offers a relatively ... More
A New Push-Relabel Algorithm for Sparse NetworksOct 29 2013Jun 10 2014In this paper, we present a new push-relabel algorithm for the maximum flow problem on flow networks with $n$ vertices and $m$ arcs. Our algorithm computes a maximum flow in $O(mn)$ time on sparse networks where $m = O(n)$. To our knowledge, this is the ... More
From ageing to immortality: cluster growth in stirred colloidal solutionsNov 27 2004This model describes cluster aggregation in a stirred colloidal solution Interacting clusters compete for growth in this 'winner-takes-all' model; for finite assemblies, the largest cluster always wins, i.e. there is a uniform sediment. In mean-field, ... More
Numerical Polynomial Homotopy Continuation Method and String VacuaAug 04 2011Dec 14 2011Finding vacua for the four dimensional effective theories for supergravity which descend from flux compactifications and analyzing them according to their stability is one of the central problems in string phenomenology. Except for some simple toy models, ... More
Sophisticated gamblers ruin and survival chancesMar 24 2014This note explores the mathematical theory to solve modern gamblers ruin problems. We establish a ruin framework and solve for the probability of bankruptcy. We also show how this relates to the expected time to bankruptcy and review the risk neutral ... More
Topological phase in two flavor neutrino oscillationsJan 07 2009May 20 2009We show that the phase appearing in neutrino flavor oscillation formulae has a geometric and topological contribution. We identify a topological phase appearing in the two flavor neutrino oscillation formula using Pancharatnam's prescription of quantum ... More
Hodge structure on the cohomology of the moduli space of Higgs bundlesDec 12 2001Nov 27 2002We study the moduli space of Higgs bundles on a compact Riemann surface. It was shown by Thaddeus and Hausel (in rank 2) and Markman (in general rank) that the rational cohomology ring of this space is generated by universal classes. In this paper, we ... More
Constant Rank Bimatrix Games are PPAD-hardFeb 14 2014Mar 22 2014The rank of a bimatrix game (A,B) is defined as rank(A+B). Computing a Nash equilibrium (NE) of a rank-$0$, i.e., zero-sum game is equivalent to linear programming (von Neumann'28, Dantzig'51). In 2005, Kannan and Theobald gave an FPTAS for constant rank ... More
Max-Flows on Sparse and Dense NetworksSep 10 2013Oct 29 2013In this paper, we present an improved algorithm for the maximum flow problem on general networks with $n$ vertices and $m$ arcs. We show how to solve the problem in $O(mn)$ time, when $m = O(n^{2-\epsilon})$, for some $0 <\epsilon \leq 1$. This improves ... More
The L1 norm of the generalized de la Vallee Poussin kernelNov 05 2013Charles de la Vall'ee Poussin defined two different kernels that bear his name. This paper considers the one are a linear combinations of two Fej'er kernels, which are known as the delayed means. We show that the $L^1$ norms are constant in families of ... More
Cryptanalysis of a Chaotic Image Encryption AlgorithmJan 01 2008Jan 12 2008Line map, an invertible, two-dimensional chaotic encryption algorithm was introduced recently. In this paper, we propose several weaknesses of the method based on standard cryptanalytic attacks. We perform a side-channel attack by observing the execution ... More
Generating Simulations of Motion Events from Verbal DescriptionsOct 06 2016In this paper, we describe a computational model for motion events in natural language that maps from linguistic expressions, through a dynamic event interpretation, into three-dimensional temporal simulations in a model. Starting with the model from ... More
Designing Optimal Binary Rating SystemsJun 18 2018Apr 07 2019Modern online platforms rely on effective rating systems to learn about items. We consider the optimal design of rating systems that collect binary feedback after transactions. We make three contributions. First, we formalize the performance of a rating ... More
On the discrepancy of random low degree set systemsOct 08 2018Motivated by the celebrated Beck-Fiala conjecture, we consider the random setting where there are $n$ elements and $m$ sets and each element lies in $t$ randomly chosen sets. In this setting, Ezra and Lovett showed an $O((t \log t)^{1/2})$ discrepancy ... More
Potential-Function Proofs for First-Order MethodsDec 13 2017Mar 07 2019This note discusses proofs for convergence of first-order methods based on simple potential-function arguments. We cover methods like gradient descent (for both smooth and non-smooth settings), mirror descent, and some accelerated variants.
Asymptotically Optimal Multi-PavingJun 12 2017Aug 23 2017Anderson's paving conjecture, now known to hold due to the resolution of the Kadison-Singer problem asserts that every zero diagonal Hermitian matrix admits non-trivial pavings with dimension independent bounds. In this paper, we develop a technique extending ... More
Spectral weight in Chern-Simons theory with symmetry breakingMay 17 2019We calculate the low-energy spectral weight of a holographic superfluid coupled to a Chern-Simons term in IR radial scaling geometries characterized by a parameter $\eta$. This work was motivated by previous results where an unexpected low-energy spectral ... More
Hadronic Screening in Improved TasteFeb 20 2013We present our results on meson and nucleon screening masses in finite temperature two flavour QCD using smeared staggered valence quarks and staggered thin-link sea quarks with different lattice spacings and quark masses. We investigate optimization ... More
External Photoevaporation of the Solar Nebula: Jupiter's Noble Gas EnrichmentsOct 17 2014We present a model explaining elemental enrichments in Jupiter's atmosphere, particularly the noble gases Ar, Kr, and Xe. While He, Ne and O are depleted, seven other elements show similar enrichments ($\sim$3 times solar, relative to H). Being volatile, ... More
Algorithmic Discrepancy Beyond Partial ColoringNov 06 2016The partial coloring method is one of the most powerful and widely used method in combinatorial discrepancy problems. However, in many cases it leads to sub-optimal bounds as the partial coloring step must be iterated a logarithmic number of times, and ... More
Designing Informative Rating Systems for Online Platforms: Evidence from Two ExperimentsOct 30 2018Platforms critically rely on rating systems to learn the quality of market participants. In practice, however, these ratings are often highly inflated, drastically reducing the signal available to distinguish quality. We consider two questions: First, ... More
Including parameter dependence in the data and covariance for cosmological inferenceAug 03 2015Jan 05 2016The final step of most large-scale structure analyses involves the comparison of power spectra or correlation functions to theoretical models. It is clear that the theoretical models have parameter dependence, but frequently the measurements and the covariance ... More
No evidence for bilinear condensate in parity-invariant three-dimensional QED with massless fermionsDec 09 2015Feb 04 2016We present our numerical study of three-dimensional QED with 2, 4, 6 and 8 flavors of massless two-component fermions using a parity-preserving lattice regularization with Wilson fermions. We study the behavior of low-lying eigenvalues of the massless ... More
The equation of state of two dimensional Yang-Mills theoryNov 10 2014We study the pressure, $P$, of SU($N$) gauge theory on a two-dimensional torus as a function of area, $A=l/t$. We find a cross-over scale that separates the system on a large circle from a system on a small circle at any finite temperature. The cross-over ... More
Bilinear condensate in three-dimensional large-$N_c$ QCDJul 13 2016We find clear numerical evidence for a bilinear condensate in three-dimensional QCD in the 't Hooft limit. We use a non-chiral random matrix model to extract the value of the condensate $\Sigma$ from the low-lying eigenvalues of the massless anti-Hermitian ... More
Driver Surge PricingMay 18 2019Uber and Lyft ride-hailing marketplaces use dynamic pricing, often called surge, to balance the supply of available drivers with the demand for rides. We study pricing mechanisms for such marketplaces from the perspective of drivers, presenting the theoretical ... More
Complexity Bounds for the Controllability of Temporal Networks with Conditions, Disjunctions, and UncertaintyJan 08 2019In temporal planning, many different temporal network formalisms are used to model real world situations. Each of these formalisms has different features which affect how easy it is to determine whether the underlying network of temporal constraints is ... More
A Universal Parallel Two-Pass MDL Context Tree Compression AlgorithmJul 06 2014Mar 21 2015Computing problems that handle large amounts of data necessitate the use of lossless data compression for efficient storage and transmission. We present a novel lossless universal data compression algorithm that uses parallel computational units to increase ... More
Stability of the Kepler-11 System and its OriginAug 29 2014A significant fraction of Kepler systems are closely-packed, largely coplanar and circular. We study the stability of a 6-planet system, Kepler-11, to gain insights on the dynamics and formation history of such systems. Using a technique called `frequency ... More
Content Replication in Large Distributed CachesMar 30 2016In this paper, we consider the algorithmic task of content replication and request routing in a distributed caching system consisting of a central server and a large number of caches, each with limited storage and service capabilities. We study a time-slotted ... More
Designing Optimal Binary Rating SystemsJun 18 2018Oct 28 2018Modern online platforms rely on effective rating systems to learn about items. We consider the optimal design of rating systems that collect {\em binary feedback} after transactions. We make three contributions. First, we formalize the performance of ... More
Learning-Based Proxy Collision Detection for Robot Motion Planning ApplicationsFeb 21 2019This paper demonstrates that collision detection-intensive applications such as robotic motion planning may be accelerated by performing collision checks with a machine learning model. We propose Fastron, a learning-based algorithm to model a robot's ... More
Bounded Treewidth and Space-Efficient Linear AlgebraDec 08 2014Motivated by a recent result of Elberfeld, Jakoby and Tantau showing that $\mathsf{MSO}$ properties are Logspace computable on graphs of bounded tree-width, we consider the complexity of computing the determinant of the adjacency matrix of a bounded tree-width ... More
Gravitational Lensing In Case of Massive ParticlesNov 30 2003Gravitation lensing calculations, which are generally done for light ray, are extended to that for a massive particle. Many interesting results were observed. We discuss the scattering cross section along-with many consequential quantities here. In particular, ... More
Approximation-Friendly Discrepancy RoundingDec 07 2015Rounding linear programs using techniques from discrepancy is a recent approach that has been very successful in certain settings. However this method also has some limitations when compared to approaches such as randomized and iterative rounding. We ... More
Evaluating the Performance of Offensive Linemen in the NFLMar 24 2016Apr 10 2016How does one objectively measure the performance of an individual offensive lineman in the NFL? The existing literature proposes various measures that rely on subjective assessments of game film, but has yet to develop an objective methodology to evaluate ... More
VoxML: A Visualization Modeling LanguageOct 05 2016We present the specification for a modeling language, VoxML, which encodes semantic knowledge of real-world objects represented as three-dimensional models, and of events and attributes related to and enacted over these objects. VoxML is intended to overcome ... More
Flavor and topological current correlators in parity-invariant three-dimensional QEDMay 31 2017We use lattice regularization to study the flow of the flavor-triplet fermion current central charge $C^f_J$ from its free field value in the ultraviolet limit to its conformal value in the infrared limit of the parity-invariant three-dimensional QED ... More
Geometry of Scheduling on Multiple MachinesJul 11 2019We consider the following general scheduling problem: there are $m$ identical machines and $n$ jobs all released at time $0$. Each job $j$ has a processing time $p_j$, and an arbitrary non-decreasing function $f_j$ that specifies the cost incurred for ... More
Imperfect Gaps in Gap-ETH and PCPsJul 18 2019We study the role of perfect completeness in probabilistically checkable proof systems (PCPs) and give a new way to transform a PCP with imperfect completeness to a PCP with perfect completeness when the initial gap is a constant. In particular, we show ... More
UV Suppression by Smearing and Screening CorrelatorsNov 20 2013We investigate the mechanism of smearing in the APE, Stout, HYP and HEX schemes through their effect on glue and quark Fourier modes. Using this, we non-perturbatively tune the smearing parameters to their optimum values. Smearing causes a super-linear ... More
A Review Paper on Oculus Rift-A Virtual Reality HeadsetAug 06 2014Oculus rift: Virtual reality (VR) is a burgeoning field that has the inherent potential of manipulating peoples mind with a superlative 3D experience. Oculus rift is one such application that assists in achieving the same. With the fleeting enhancements ... More
A New Class of Combinatorial Markets with Covering Constraints: Algorithms and ApplicationsNov 27 2015Apr 13 2017We introduce a new class of combinatorial markets in which agents have covering constraints over resources required and are interested in delay minimization. Our market model is applicable to several settings including scheduling, cloud computing, and ... More
A 2% Distance to z = 0.35 by Reconstructing Baryon Acoustic Oscillations - III : Cosmological Measurements and InterpretationFeb 01 2012Mar 28 2012We use the 2% distance measurement from our reconstructed baryon acoustic oscillations (BAOs) signature using the Sloan Digital Sky Survey (SDSS) Data Release 7 (DR7) Luminous Red Galaxies (LRGs) from Padmanabhan et al. (2012) and Xu et al. (2012) combined ... More
A Market for Scheduling, with Applications to Cloud ComputingNov 27 2015We present a market for allocating and scheduling resources to agents who have specified budgets and need to complete specific tasks. Two important aspects required in this market are: (1) agents need specific amounts of each resource to complete their ... More
A 2% Distance to z=0.35 by Reconstructing Baryon Acoustic Oscillations - II: Fitting TechniquesFeb 01 2012Feb 04 2012We present results from fitting the baryon acoustic oscillation (BAO) signal in the correlation function obtained from the first application of reconstruction to a galaxy redshift survey, namely, the Sloan Digital Sky Survey (SDSS) Data Release 7 (DR7) ... More
Zeros of some bi-orthogonal polynomialsSep 04 2001Ercolani and McLaughlin have recently shown that the zeros of the bi-orthogonal polynomials with the weight $w(x,y)=\exp[-(V_1(x)+V_2(y)+2cxy)/2]$, relevant to a model of two coupled hermitian matrices, are real and simple. We show that their argument ... More
On exact minimization of Higgs potentialsJul 05 2013May 29 2014Minimizing the Higgs potential is an essential task in any model involving Higgs bosons. Exact minimization methods proposed in the literature are based on the polynomial form of the potential. These methods will in general no longer work if loop contributions ... More
Identifying feasible operating regimes for early T-cell recognition: The speed, energy, accuracy trade-off in kinetic proofreading and adaptive sortingMar 09 2017Aug 16 2018In the immune system, T cells can quickly discriminate between foreign and self ligands with high accuracy. There is evidence that T-cells achieve this remarkable performance utilizing a network architecture based on a generalization of kinetic proofreading ... More
The clash of the Titans: how preferential attachment helps the survival of the smallestMar 31 2014We examine the effects of preferential attachment on a model of competing clusters. In the original model, cluster masses grow at the expense of their neighbours; on a lattice, this is known to result in the asymptotic survival and indefinite growth of ... More
On random graphs and the statistical mechanics of granular matterDec 21 2000Oct 19 2001The dynamics of spins on a random graph with ferromagnetic three-spin interactions is used to model the compaction of granular matter under a series of taps. Taps are modelled as the random flipping of a small fraction of the spins followed by a quench ... More
Learning theories reveal loss of pancreatic electrical connectivity in diabetes as an adaptive responseJun 29 2013Cells of almost all solid tissues are connected with gap junctions which permit the direct transfer of ions and small molecules, integral to regulating coordinated function in the tissue. The pancreatic islets of Langerhans are responsible for secreting ... More
Competing with oneself: Introducing self-interaction in a model of competitive learningJan 11 2010Aug 27 2010A competitive learning model was introduced in Ref. 1 (A. Mehta and J. M. Luck, Phys. Rev. E 60, 5, 1999), in which the learning is outcome-related. Every individual chooses between a pair of existing strategies or types, guided by a combination of two ... More
Minimizing Higgs Potentials via Numerical Polynomial Homotopy ContinuationMar 02 2012The study of models with extended Higgs sectors requires to minimize the corresponding Higgs potentials, which is in general very difficult. Here, we apply a recently developed method, called numerical polynomial homotopy continuation (NPHC), which guarantees ... More
Nonequilibrium quantum-impurities: from entropy production to information theoryMay 31 2007Jun 08 2007Nonequilibrium steady-state currents, unlike their equilibrium counterparts, continuously dissipate energy into their physical surroundings leading to entropy production and time-reversal symmetry breaking. This letter discusses these issues in the context ... More
Scattering approach to impurity thermodynamicsFeb 26 2007Feb 26 2007Recently the authors developed a scattering approach that allows for a complete description of the steady-state physics of quantum-impurities in and out of equilibrium. Quantum impurities are described using scattering eigenstates defined ab initio on ... More
Lie algebroid modules and representations up to homotopyJul 07 2011Sep 08 2014We establish a relationship between two different generalizations of Lie algebroid representations: representation up to homotopy and Vaintrob's Lie algebroid modules. Specifically, we show that there is a noncanonical way to obtain a representation up ... More
Birational invariance of the $S$-fundamental group schemeJun 28 2010Let $X$ and $Y$ be nonsingular projective varieties over an algebraically closed field $k$ of positive characteristic. If $X$ and $Y$ are birational, we show their $S$-fundamental group schemes are isomorphic.
Fundamental Limits of Video Coding: A Closed-form Characterization of Rate Distortion Region from First PrinciplesFeb 27 2014Classical motion-compensated video coding methods have been standardized by MPEG over the years and video codecs have become integral parts of media entertainment applications. Despite the ubiquitous use of video coding techniques, it is interesting to ... More
Enumerating Copies in the First Gribov Region on the Lattice in up to four DimensionsMar 03 2014May 20 2014The covariant gauges are known to suffer from the Gribov problem: even after fixing a gauge non-perturbatively, there may still exist residual copies which are physically equivalent to each other, called Gribov copies. While the influence of Gribov copies ... More
Products of Farey FractionsMar 01 2015May 09 2017The {Farey fractions} $F_n$ of order $n$ consist of all fractions $\frac{h}{k}$ in lowest terms lying in the closed unit interval and having denominator at most $n$. This paper considers the products $F_n$ of all nonzero Farey fractions of order $n$. ... More
Exploiting local and global performance of candidate systems for aggregation of summarization techniquesSep 07 2018With an ever growing number of extractive summarization techniques being proposed, there is less clarity then ever about how good each system is compared to the rest. Several studies highlight the variance in performance of these systems with change in ... More
Content based Weighted Consensus SummarizationFeb 03 2018Multi-document summarization has received a great deal of attention in the past couple of decades. Several approaches have been proposed, many of which perform equally well and it is becoming in- creasingly difficult to choose one particular system over ... More
Non-standard interactions and the resolution of ordering of neutrino masses at DUNE and other long baseline experimentsJun 17 2016Sep 10 2016In the era of precision neutrino physics, we study the influence of matter NSI on the question of neutrino mass ordering and its resolution. At long baseline experiments, since matter effects play a crucial role in addressing this very important question, ... More
Q-groupoids and their cohomologyNov 29 2006Oct 17 2011We approach Mackenzie's LA-groupoids from a supergeometric point of view by introducing Q-groupoids, which are groupoid objects in the category of Q-manifolds. There is a faithful functor from the category of LA-groupoids to the category of Q-groupoids. ... More
Cosmological production of H_2 before the formation of the first galaxiesJun 19 2006Previous calculations of the pregalactic chemistry have found that a small amount of H_2, x[H_2]=n[H_2]/n[H] = 2.6e-6, is produced catalytically through the H^-, H_2^+, and HeH^+ mechanisms. We revisit this standard calculation taking into account the ... More
Weak Lensing Constraints on Cluster Structural ParametersDec 12 2000We study the reliability of dark matter (DM) profile determinations for rich clusters of galaxies based on weak gravitational lensing measurements. We consider three functional forms for the mass distribution: a softened isothermal sphere (SIS), the Navarro, ... More
Detecting Dark Matter Annihilation with CMB Polarization : Signatures and Experimental ProspectsMar 23 2005Dark matter (DM) annihilation during hydrogen recombination (z ~ 1000) will alter the recombination history of the Universe, and affect the observed CMB temperature and polarization fluctuations. Unlike other astrophysical probes of DM, this is free of ... More
Linear Contextual Bandits with KnapsacksJul 24 2015Jul 09 2016We consider the linear contextual bandit problem with resource consumption, in addition to reward generation. In each round, the outcome of pulling an arm is a reward as well as a vector of resource consumptions. The expected values of these outcomes ... More
Faster Space-Efficient Algorithms for Subset Sum, k-Sum and Related ProblemsDec 08 2016We present space efficient Monte Carlo algorithms that solve Subset Sum and Knapsack instances with $n$ items using $O^*(2^{0.86n})$ time and polynomial space, where the $O^*(\cdot)$ notation suppresses factors polynomial in the input size. Both algorithms ... More
Precision Pointing of Antennas in Space Using Arrays of Shape Memory Alloy Based Linear ActuatorsJan 26 2017Space systems such as communication satellites, earth observation satellites and space telescopes require precise pointing to observe fixed targets over prolonged time. These systems typically use reaction-wheels to slew the spacecraft and gimballing ... More
Fast Algorithms for Online Stochastic Convex ProgrammingOct 28 2014We introduce the online stochastic Convex Programming (CP) problem, a very general version of stochastic online problems which allows arbitrary concave objectives and convex feasibility constraints. Many well-studied problems like online stochastic packing ... More
The Gauss-Bonnet-Chern theorem: a probabilistic perspectiveApr 21 2014Jan 18 2016We prove that the Euler form of a metric connection on real oriented vector bundle $E$ over a compact oriented manifold $M$ can be identified, as a current, with the expectation of the random current defined by the zero-locus of a certain random section ... More
R-Estimation for Asymmetric Independent Component AnalysisApr 10 2013Dec 13 2013Independent Component Analysis (ICA) recently has attracted attention in the statistical literature as an alternative to elliptical models. Whereas k-dimensional elliptical densities depend on one single unspecified radial density, however, k-dimensional ... More
Non-standard interactions spoiling the CP violation sensitivity at DUNE and other long baseline experimentsMar 04 2016Jul 12 2016It is by now established that neutrino oscillations occur due to non-zero masses and parameters in the leptonic mixing matrix. The extraction of oscillation parameters may be complicated due to subleading effects such as non-standard neutrino interactions ... More
Efficiency bounds for nonequilibrium heat enginesJul 24 2012Jan 22 2013We analyze the efficiency of thermal engines (either quantum or classical) working with a single heat reservoir like atmosphere. The engine first gets an energy intake, which can be done in arbitrary non-equilibrium way e.g. combustion of fuel. Then the ... More
Interplay of energy dependent astrophysical neutrino flavor ratios and new physics effectsJan 13 2011Mar 25 2011We discuss the importance of flavor ratio measurements in neutrino telescopes, such as by measuring the ratio between muon tracks to cascades, for the purpose of extracting new physics signals encountered by astrophysical neutrinos during propagation ... More
Nonequilibrium Transport in Quantum Impurity Models (Bethe-Ansatz for open systems)Jul 31 2005Dec 02 2005We develop an exact non-perturbative framework to compute steady-state properties of quantum-impurities subject to a finite bias. We show that the steady-state physics of these systems is captured by nonequilibrium scattering eigenstates which satisfy ... More
Fast rates with high probability in exp-concave statistical learningMay 04 2016Oct 14 2016We present an algorithm for the statistical learning setting with a bounded exp-concave loss in $d$ dimensions that obtains excess risk $O(d \log(1/\delta)/n)$ with probability at least $1 - \delta$. The core technique is to boost the confidence of recent ... More
Born-Oppenheimer study of two-component few-particle systems under one-dimensional confinementJan 14 2014Apr 28 2014The energy spectrum, atom-dimer scattering length, and atom-trimer scattering length for systems of three and four ultracold atoms with $\delta$-function interactions in one dimension are presented as a function of the relative mass ratio of the interacting ... More
Rationality of the instability parabolic and related resultsNov 11 2011In this paper we study the extension of structure group of principal bundles with a reductive algebraic group as structure group on smooth projective varieties defined over algebraically closed field of positive characteristic. Our main result is to show ... More
Differential graded contact geometry and Jacobi structuresNov 21 2011Aug 18 2013We study contact structures on nonnegatively-graded manifolds equipped with homological contact vector fields. In the degree 1 case, we show that there is a one-to-one correspondence between such structures (with fixed contact form) and Jacobi manifolds. ... More
An index-resolved fixed-point homotopy and potential energy landscapesApr 24 2015Stationary points (SPs) of the potential energy landscapes can be classified by their Morse index, i.e., the number of negative eigenvalues of the Hessian evaluated at the SPs. In understanding chemical clusters through their potential energy landscapes, ... More
The Storage-Repair-Bandwidth Trade-off of Exact Repair Linear Regenerating Codes for the Case $d = k = n-1$Jan 16 2015Jan 26 2015In this paper, we consider the setting of exact repair linear regenerating codes. Under this setting, we derive a new outer bound on the storage-repair-bandwidth trade-off for the case when $d = k = n -1$, where $(n, k, d)$ are parameters of the regenerating ... More
Bandits with concave rewards and convex knapsacksFeb 24 2014In this paper, we consider a very general model for exploration-exploitation tradeoff which allows arbitrary concave rewards and convex constraints on the decisions across time, in addition to the customary limitation on the time horizon. This model subsumes ... More
Binarizer at SemEval-2018 Task 3: Parsing dependency and deep learning for irony detectionMay 03 2018In this paper, we describe the system submitted for the SemEval 2018 Task 3 (Irony detection in English tweets) Subtask A by the team Binarizer. Irony detection is a key task for many natural language processing works. Our method treats ironical tweets ... More
Stable Prehensile Pushing: In-Hand Manipulation with Alternating Sticking ContactsOct 30 2017Mar 04 2018This paper presents an approach to in-hand manipulation planning that exploits the mechanics of alternating sticking contact. Particularly, we consider the problem of manipulating a grasped object using external pushes for which the pusher sticks to the ... More
Regrasping by Fixtureless FixturingSep 23 2018Sep 25 2018This paper presents a fixturing strategy for regrasping that does not require a physical fixture. To regrasp an object in a gripper, a robot pushes the object against external contact/s in the environment such that the external contact keeps the object ... More
An Information Theoretic Approach Towards Assessing Perceptual Audio Quality using EEGSep 14 2015In this paper, we propose a novel information theoretic model to interpret the entire "transmission chain" comprising stimulus generation, brain processing by the human subject, and the electroencephalograph (EEG) response measurements as a nonlinear, ... More
Modular Classes of Lie Groupoid Representations up to HomotopyFeb 22 2015Jul 25 2015We describe a construction of the modular class associated to a representation up to homotopy of a Lie groupoid. In the case of the adjoint representation up to homotopy, this class is the obstruction to the existence of a volume form, in the sense of ... More
A Survey on Resilient Machine LearningJul 11 2017Machine learning based system are increasingly being used for sensitive tasks such as security surveillance, guiding autonomous vehicle, taking investment decisions, detecting and blocking network intrusion and malware etc. However, recent research has ... More
Semistability of Frobenius direct images over curvesJul 22 2006Let $X$ be a smooth projective curve of genus $g \geq 2$ defined over an algebraically closed field $k$ of characteristic $p>0$. Given a semistable vector bundle $E$ over $X$, we show that its direct image $F\_*E$ under the Frobenius map $F$ of $X$ is ... More
Stueckelberg Bosons as an Ultralight Dark Matter CandidateFeb 23 2019In this letter, we propose a new model of fuzzy dark matter based on Stueckelberg theory. Dark matter is treated as a Bose-Einstein condensate of Stueckelberg particles and the resulting cosmological effects are analyzed. Fits are understood for the density ... More
Infrared Effects and the Soft Photon Theorem in Massive QEDOct 24 2018Stueckelberg QED with massive photon is known to be renormalizable. But the limit of the mass going to zero is interesting because it brings the resolution to infrared questions through the role of Stueckelberg field at null infinity in addition to providing ... More
Sampling-based Planning of In-Hand Manipulation with External PushesJul 02 2017Nov 02 2017This paper presents a sampling-based planning algorithm for in-hand manipulation of a grasped object using a series of external pushes. A high-level sampling-based planning framework, in tandem with a low-level inverse contact dynamics solver, effectively ... More
Optimizing a jump-diffusion model of a starving foragerJul 18 2018We analyze the movement of a starving forager on a one-dimensional periodic lattice, where each location contains one unit of food. As the forager lands on sites with food, it consumes the food, leaving the sites empty. If the forager lands consecutively ... More