Results for "Pranjal Trivedi"

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Axion-like Dark Matter Constraints from CMB BirefringenceNov 19 2018Axion-like particles are dark matter candidates motivated by the Peccei-Quinn mechanism and also occur in effective field theories where their masses and photon couplings are independent. We estimate the dispersion of circularly polarized photons in a ... More
Axion Condensate Dark Matter Constraints from Resonant Enhancement of Background RadiationJul 10 2019We investigate the possible parametric growth of photon amplitudes in a background of axion-like particle (ALP) dark matter. The observed extragalactic background radiation limits the allowed enhancement effect. We derive the resulting constraints on ... More
Primordial Magnetic Field Limits from Cosmic Microwave Background Bispectrum of Magnetic Passive Scalar ModesSep 14 2010Primordial magnetic fields lead to non-Gaussian signals in the cosmic microwave background (CMB) even at the lowest order, as magnetic stresses and the temperature anisotropy they induce depend quadratically on the magnetic field. In contrast, CMB non-Gaussianity ... More
Primordial Magnetic Field Limits from CMB Trispectrum - Scalar Modes and Planck ConstraintsDec 18 2013Cosmic magnetic fields are observed to be coherent on large scales and could have a primordial origin. Non-Gaussian signals in the cosmic microwave background (CMB) are generated by primordial magnetic fields as the magnetic stresses and temperature anisotropy ... More
Cosmic Microwave Background Trispectrum and Primordial Magnetic Field LimitsNov 03 2011Jun 14 2012Primordial magnetic fields will generate non-Gaussian signals in the cosmic microwave background (CMB) as magnetic stresses and the temperature anisotropy they induce depend quadratically on the magnetic field. We compute a new measure of magnetic non-Gaussianity, ... More
Magnetic heating across the cosmological recombination era: Results from 3D MHD simulationsMay 14 2018The origin of cosmic magnetic fields is an unsolved problem and magnetogenesis could have occurred in the early Universe. We study the evolution of such primordial magnetic fields across the cosmological recombination epoch via 3D magnetohydrodynamic ... More
Improved Spectral-Norm Bounds for ClusteringJun 14 2012Jun 15 2012Aiming to unify known results about clustering mixtures of distributions under separation conditions, Kumar and Kannan[2010] introduced a deterministic condition for clustering datasets. They showed that this single deterministic condition encompasses ... More
Revisiting AdS/CFT at a finite radial cut-offAug 01 2016We revisit AdS/CFT at finite radial cut-off, specifically in the context of double trace perturbations, $\mathbb{O}_n$= $\mathbb{O}(x) (\partial^2)^{n} {\mathcal O}(x)$, with arbitrary $n$. As well-known, the standard GKPW prescription, applied to a finite ... More
Fast Evaluation of Multi-Hadron Correlation FunctionsNov 13 2014Calculating the values of nuclear correlation functions is computationally intensive due to the fact that the number of terms in a nuclear wave function scales exponentially with atomic number. To speed up this computation, we represent a correlation ... More
Conformal properties of soft operators - 2 : Use of null-statesJun 04 2019Representations of the (Lorentz) conformal group with the soft operators as highest weight vectors have two universal properties, which we clearly state in this paper. Given a soft operator with a certain dimension and spin, the first property is about ... More
On some provably correct cases of variational inference for topic modelsMar 23 2015Aug 22 2015Variational inference is a very efficient and popular heuristic used in various forms in the context of latent variable models. It's closely related to Expectation Maximization (EM), and is applied when exact EM is computationally infeasible. Despite ... More
Color reconnection as a possible mechanism of intermittency in the emission spectra of charged particles in PYTHIA-generated high-multiplicity $\textit{pp}$ collisions at energies available at the CERN Large Hadron ColliderFeb 25 2019Nonstatistical fluctuation in pseudorapidity ($\eta$), azimuthal ($\phi$), and pseudorapidity-azimuthal ($\eta-\phi$) distribution spectra of primary particles of PYTHIA Monash (default) generated $pp$ events at $\sqrt{s}=$ 2.76, 7, and 13 TeV have been ... More
Revisiting AdS/CFT at a finite radial cut-offAug 01 2016Dec 13 2016We revisit AdS/CFT at finite radial cut-off, specifically in the context of double trace perturbations, $\mathbb{O}_n$= $\mathbb{O}(x) (\partial^2)^{n} {\mathcal O}(x)$, with arbitrary $n$. As well-known, the standard GKPW prescription, applied to a finite ... More
Words are not Equal: Graded Weighting Model for building Composite Document VectorsDec 11 2015Despite the success of distributional semantics, composing phrases from word vectors remains an important challenge. Several methods have been tried for benchmark tasks such as sentiment classification, including word vector averaging, matrix-vector approaches ... More
Frobenius pull backs of vector bundles in higher dimensionsNov 09 2010Dec 17 2010Here we prove that for a smooth projective variety $X$ of arbitrary dimension and for a vector bundle $E$ over $X$, the Harder-Narasimhan filtration of a Frobenius pull back of $E$ is a refinement of the Frobenius pull-back of the Harder-Narasimhan filtration ... More
A covariant Stinespring type theorem for $τ$-mapsOct 16 2014Jan 13 2015Let $\tau$ be a linear map from a unital $C^*$-algebra $\CMcal A$ to a von Neumann algebra $\mathematical B$ and let $\CMcal C$ be a unital $C^*$-algebra. A map $T$ from a Hilbert $\CMcal A$-module $E$ to a von Neumann $\CMcal C$-$\CMcal B$ module $F$ ... More
[Towards Hilbert-Kunz density functions in Characteristic $0$Jan 08 2016For a pair $(R, I)$, where $R$ is a standard graded domain over an algebraically closed field of characteristic $0$ and $I$ is a graded ideal with $\ell(R/I) < \infty$, we prove that, as $p\to \infty $, the convergence of the HK density function $f^p(R_p, ... More
Semistablity of syzygy bundles on projective spaces in positive characteristicsApr 03 2008Apr 24 2009In char $k = p >0$, A. Langer proved a strong restriction theorem (in the style of H. Flenner) for semistable sheaves to a very general hypersurface of degree $d$, on certain varieties, with the condition that `char $k > d$'. He remarked that to remove ... More
Temperature-dependent dielectric function of bulk SrTiO$_3$: Urbach tail, band edges, and excitonic effectsFeb 27 2016We report the temperature-dependent complex dielectric function of pristine bulk SrTiO$_3$ between 4.2 and 300 K within the energy range of 0.6-6.5 eV determined by spectroscopic ellipsometry. Fundamental indirect and direct band-gap energies have been ... More
Discriminative Learning of Similarity and Group Equivariant RepresentationsAug 30 2018One of the most fundamental problems in machine learning is to compare examples: Given a pair of objects we want to return a value which indicates degree of (dis)similarity. Similarity is often task specific, and pre-defined distances can perform poorly, ... More
Towards Hilbert-Kunz density functions in Characteristic $0$Jan 08 2016Jan 26 2017For a pair $(R, I)$, where $R$ is a standard graded domain of dimension $d$ over an algebraically closed field of characteristic $0$ and $I$ is a graded ideal of finite colength, we prove that the existence of $\lim_{p\to \infty}e_{HK}(R_p, I_p)$ is equivalent, ... More
A simple proof of the fixed point theorem in $C^*$-algebra valued metric spaceAug 13 2017We obtain a fundamental inequality for a contraction with respect to a $C^*$-algebra valued metric space. As an application of this inequality a simple proof is given for the fixed point theorem in $C^*$-algebra valued metric space.
Hilbert-Kunz density function and Hilbert-Kunz multiplicityOct 12 2015Nov 04 2015For a pair $(M, I)$, where $M$ is finitely generated graded module over a standard graded ring $R$ of dimension $d$, and $I$ is a graded ideal with $\ell(R/I) < \infty$, we introduce a new invariant $HKd(M, I)$ called the {\em Hilbert-Kunz density function}. ... More
Transversality theorems for the weak topologyOct 10 2011In his 1979 paper Trotman proves, using the techniques of the Thom transversality theorem, that under some conditions on the dimensions of the manifolds under consideration, openness of the set of maps transverse to a stratification in the strong (Whitney) ... More
A characterization of Whitney a-regular complex analytic stratificationsSep 06 2012Dec 09 2012We prove that the openness of the set of maps, between a Stein manifold and an Oka manifold, transverse to a stratification of a complex analytic subvariety in the target implies that the stratification is Whitney $a$-regular. Our result can be seen as ... More
Semistability and Hilbert-Kunz multiplicities for curvesFeb 15 2004Dec 13 2004We study Hilbert-Kunz multiplicity of non-singular curves in positive characteristic. We analyse the relationship between the Frobenius semistability of the kernel sheaf associated with the curve and its ample line bundle, and the HK multiplicity. This ... More
Hilbert-Kunz multiplicity and reduction mod pJul 29 2004Mar 30 2005We show that the Hilbert-Kunz multiplicities of the reductions to positive characteristics of an irreducible projective curve in characteristic 0 have a well-defined limit as the characteristic tends to infinity.
Arithmetic behaviour of Frobenius semistability of syzygy bundles for plane trinomial curvesJan 25 2017Jan 26 2017Here we consider the set of bundles $\{V_n\}_{n\geq 1}$ associated to the plane trinomial curves $k[x,y,z]/(h)$. We prove that the Frobenius semistability behaviour of the reduction mod $p$ of $V_n$ is a function of the congruence class of $p$ modulo ... More
Cohomology of flat currents on definable pseudomanifoldsOct 05 2016May 27 2018We show that the cohomology of flat currents on definable pseudomanifolds in polynomially bounded o-minimal structures is isomorphic to its intersection cohomology in the top perversity.
Hilbert-Kunz density function and Hilbert-Kunz multiplicityOct 12 2015Jul 05 2017For a pair $(M, I)$, where $M$ is finitely generated graded module over a standard graded ring $R$ of dimension $d$, and $I$ is a graded ideal with $\ell(R/I) < \infty$, we introduce a new invariant $HKd(M, I)$ called the {\em Hilbert-Kunz density function}. ... More
Hilbert-Kunz functions of a Hirzebruch surfaceJul 23 2014Sep 23 2015Here we compute Hilbert-Kunz functions of any nontrivial ruled surface over ${\bf P}^1_k$, with respect to all ample line bundles on it.
Nondiscreteness of $F$-thresholdsAug 22 2018We give examples of two dimensional normal ${\mathbb Q}$-Gorenstein graded domains, where the set of $F$-thresholds of the maximal ideal is not discrete, thus answering a question by Musta\c{t}\u{a}-Takagi-Watanabe. We also prove that, for a two dimensional ... More
On the Dynamics of Near-Extremal Black HolesFeb 26 2018Sep 13 2018We analyse the dynamics of near-extremal Reissner-Nordstr\"om black holes in asymptotically four-dimensional Anti-de Sitter space (AdS$_4$). We work in the spherically symmetric approximation and study the thermodynamics and the response to a probe scalar ... More
Eigenstate Thermalisation in the conformal Sachdev-Ye-Kitaev model: an analytic approachMar 01 2019The Sachdev-Ye-Kitaev (SYK) model provides an uncommon example of a chaotic theory that can be analysed analytically. In the deep infrared limit, the original model has an emergent conformal (reparametrisation) symmetry that is broken both spontaneously ... More
Learning using Local Membership QueriesNov 05 2012Apr 17 2013We introduce a new model of membership query (MQ) learning, where the learning algorithm is restricted to query points that are \emph{close} to random examples drawn from the underlying distribution. The learning model is intermediate between the PAC ... More
Center-based Clustering under Perturbation StabilitySep 18 2010Aug 11 2011Clustering under most popular objective functions is NP-hard, even to approximate well, and so unlikely to be efficiently solvable in the worst case. Recently, Bilu and Linial \cite{Bilu09} suggested an approach aimed at bypassing this computational barrier ... More
Late decaying 2-component dark matter scenario as an explanation of the AMS-02 positron excessSep 15 2016The long standing anomaly in the positron flux as measured by the PAMELA and AMS-02 experiments could potentially be explained by dark matter annihilations. This scenario typically requires a large "boost factor" to be consistent with a thermal relic ... More
Local algorithms for interactive clusteringDec 24 2013Mar 19 2015We study the design of interactive clustering algorithms for data sets satisfying natural stability assumptions. Our algorithms start with any initial clustering and only make local changes in each step; both are desirable features in many applications. ... More
Reheating in two-sector cosmologyJun 06 2019We analyze reheating scenarios where a hidden sector is populated during reheating along with the sector containing the Standard Model. We numerically solve the Boltzmann equations describing perturbative reheating of the two sectors, including the full ... More
A note on faithful coupling of Markov chainsOct 27 2017One often needs to turn a coupling $(X_i, Y_i)_{i\geq 0}$ of a Markov chain into a sticky coupling where once $X_T = Y_T$ at some $T$, then from then on, at each subsequent time step $T'\geq T$, we shall have $X_{T'} = Y_{T'}$. However, not all of what ... More
Proceedings of the The First Workshop on Verification and Validation of Cyber-Physical SystemsDec 13 2016The first International Workshop on Verification and Validation of Cyber-Physical Systems (V2CPS-16) was held in conjunction with the 12th International Conference on integration of Formal Methods (iFM 2016) in Reykjavik, Iceland. The purpose of V2CPS-16 ... More
Some Examples of Chiral Moduli Spaces and Dynamical Supersymmetry BreakingJul 31 1995Sep 06 1995We investigate the low-energy dynamics of $SU(N)$ gauge theories with one antisymmetric tensor field, $N - 4 + N_f$ antifundamentals and $N_f$ fundamentals, for $N_f \le 3$. For $N_f = 3$ we construct the quantum moduli space, and for $N_f < 3$ we find ... More
Generating wandering subspaces for doubly commuting covariant representations of product systemsApr 10 2019We obtain Halmos-Richter type wandering subspace theorem for covariant representations over $C^*$-correspondences. We further explore the notion of Cauchy dual and obtain Shimorin type Wold decomposition for covariant representations over $C^*$-correspondences ... More
$\mathfrak{K}$-families and CPD-H-extendable familiesSep 12 2014We introduce, for any set $S$, the concept of $\mathfrak{K}$-family between two Hilbert $C^*$-modules over two $C^*$-algebras, for a given completely positive definite (CPD-) kernel $\mathfrak{K}$ over $S$ between those $C^*$-algebras and obtain a factorization ... More
Spectral weight redistribution in strongly correlated bosons in optical latticesJan 30 2008We calculate the single-particle spectral function for the one-band Bose-Hubbard model within the random phase approximation (RPA). In the strongly correlated superfluid, in addition to the gapless phonon excitations, we find extra gapped modes which ... More
Average-Time Games on Timed AutomataOct 15 2009An average-time game is played on the infinite graph of configurations of a finite timed automaton. The two players, Min and Max, construct an infinite run of the automaton by taking turns to perform a timed transition. Player Min wants to minimise the ... More
Reachability-time games on timed automataJul 20 2009In a reachability-time game, players Min and Max choose moves so that the time to reach a final state in a timed automaton is minimised or maximised, respectively. Asarin and Maler showed decidability of reachability-time games on strongly non-Zeno timed ... More
Flat currents on definable pseudomanifoldsOct 05 2016We show that the cohomology of flat currents on definable pseudomanifolds in polynomially bounded o-minimal structures is isomorphic to its intersection cohomology in the top perversity.
A comment on effective field theories of flux vacuaAug 27 2018We discuss some basic aspects of effective field theory applied to supergravity theories which arise in the low-energy limit of string theory. Our discussion is particularly relevant to the effective field theories of no-scale supergravities that break ... More
On the Generalization of Equivariance and Convolution in Neural Networks to the Action of Compact GroupsFeb 11 2018Nov 10 2018Convolutional neural networks have been extremely successful in the image recognition domain because they ensure equivariance to translations. There have been many recent attempts to generalize this framework to other domains, including graphs and data ... More
Detecting Thom faults in stratified mappingsNov 16 2013We state and prove several characterizations of Thom's regularity condition for stratified maps. In particular we extend to stratified maps some characterizations of Whitney (a) regularity, due to the second author.
Density function for the second coefficient of the Hilbert-Kunz functionJan 22 2018We prove that, analogous to the HK density function, (used for studying the Hilbert-Kunz multiplicity, the leading coefficient of the HK function), there exists a $\beta$-density function $g_{R, {\bf m}}:[0,\infty)\longrightarrow {\mathbb R}$, where $(R, ... More
Fair k-Center Clustering for Data SummarizationJan 24 2019In data summarization we want to choose k prototypes in order to summarize a data set. We study a setting where the data set comprises several demographic groups and we are restricted to choose k_i prototypes belonging to group i. A common approach to ... More
Conformal properties of soft-operators - 1 : Use of null-statesFeb 06 2019Feb 15 2019Soft-operators, loosely speaking, are operators which create or annihilate zero energy massless particles on the celestial sphere in Minkowski space. The Lorentz group acts on the celestial sphere by conformal transformation and the soft-operators transform ... More
Inhomogeneous metallic phase upon disordering a two dimensional Mott insulatorAug 13 2003We find that isoelectronic disorder destroys the spectral gap in a Mott-Hubbard insulator in 2D leading, most unexpectedly, to a new metallic phase. This phase is spatially inhomogeneous with metallic behavior coexisting with antiferromagnetic long range ... More
Generating wandering subspaces for doubly commuting covariant representationsApr 10 2019Jul 12 2019We obtain a Halmos-Richter-type wandering subspace theorem for covariant representations of C*-correspondences. Further the notion of Cauchy dual and a version of Shimorin's Wold-type decomposition for covariant representations of C*-correspondences is ... More
Wold decomposition for Doubly commuting isometric covariant representations of product systemsMar 19 2019We obtain a complete description of reducing subspaces, of a doubly commuting isometric covariant representation of a product system of $C^*$-correspondences, as a direct summand of Hilbert spaces. This result generalize and give a new proof of the Wold ... More
The Nielsen-Ninomiya ``No-Go'' Theorem is FalseSep 18 1993Oct 04 1993The Nielsen-Ninomiya no-go theorem asserts that chiral Weyl~(``neutrino'') fields cannot exist on lattices. However, the actual mathematical arguments advanced in the theorem fail to make that case. The theorem leaves the problem of lattice neutrinos ... More
Negative differential resistance with graphene channels, interfacing distributed quantum dots in Field-Effect TransistorsJul 25 2013Field effect transistors with channels made of graphene layer(s) were explored. The graphene layer(s) contacted a distributed array of well-separated semiconductor quantum dots (QDs). The dots were embedded in nano-structured hole-array; each filled hole ... More
Semiclassical Extremal BlackholesNov 03 1992Nov 09 1992Extremal black holes are studied in a two dimensional model motivated by a dimensional reduction from four dimensions. Their quantum corrected geometry is calculated semiclassically and a mild singularity is shown to appear at the horizon. Extensions ... More
Analytic $3$-isometries without the wandering subspace propertyNov 29 2018The wandering subspace problem for an analytic norm-increasing $m$-isometry $T$ on a Hilbert space $\mathcal H$ asks whether every $T$-invariant subspace of $\mathcal H$ can be generated by a wandering subspace. An affirmative solution to this problem ... More
Deviations from Fermi-liquid behavior above $T_c$ in 2D short coherence length superconductorsNov 28 1994We show that there are qualitative differences between the temperature dependence of the spin and charge correlations in the normal state of the 2D attractive Hubbard model using quantum Monte Carlo simulations. The one-particle density of states shows ... More
An Analytic Model for Left-Invertible Weighted Shifts on Directed TreesOct 11 2015Oct 15 2015Let $\mathscr T$ be a rooted directed tree with finite branching index $k_{\mathscr T}$ and let $S_{\lambda} \in B(l^2(V))$ be a left-invertible weighted shift on ${\mathscr T}$. We show that $S_{\lambda}$ can be modelled as a multiplication operator ... More
Hilbert-Kunz density function and asymptotic Hilbert-Kunz multiplicity for projective toric varietiesJul 19 2017Aug 14 2017For a toric pair $(X, D)$, where $X$ is a projective toric variety of dimension $d-1\geq 1$ and $D$ is a very ample $T$-Cartier divisor, we show that the Hilbert-Kunz density function $HKd(X, D)(\lambda)$ is the $d-1$ dimensional volume of ${\overline ... More
Conformal properties of soft-operators - 1 : Use of null-statesFeb 06 2019Feb 07 2019Soft-operators, loosely speaking, are operators which create or annihilate zero energy massless particles on the celestial sphere in Minkowski space. The Lorentz group acts on the celestial sphere by conformal transformation and the soft-operators transform ... More
Coadjoint orbit action of Virasoro group and two-dimensional quantum gravity dual to SYK/tensor modelsFeb 14 2017Dec 29 2017The Nambu-Goldstone (NG) bosons of the SYK model are described by a coset space Diff/$\mathbb{SL}(2,\mathbb{R})$, where Diff, or Virasoro group, is the group of diffeomorphisms of the time coordinate valued on the real line or a circle. It is known that ... More
Out-of-time-ordered measurements as a probe of quantum dynamicsJan 26 2018Probing the out-of-equilibrium dynamics of quantum matter has gained renewed interest owing to immense experimental progress in artifcial quantum systems. Dynamical quantum measures such as the growth of entanglement entropy (EE) and out-of-time ordered ... More
Robust Vertex Enumeration for Convex Hulls in High DimensionsFeb 05 2018Sep 24 2018Computation of the vertices of the convex hull of a set $S$ of $n$ points in $\mathbb{R} ^m$ is a fundamental problem in computational geometry, optimization, machine learning and more. We present "All Vertex Triangle Algorithm" (AVTA), a robust and efficient ... More
Compressibility as a probe of quantum phase transitions in topological superconductorsMar 31 2015Sep 20 2015The non-Abelian statistics of Majorana fermions, their role in topological quantum computation, and the possibility of realizing them in condensed matter systems, has attracted considerable attention. While there have been recent reports of zero energy ... More
Photon Counting as a Probe of Superfluidity in a Two-Band Bose Hubbard System Coupled to a Cavity FieldNov 26 2012We show that photon number measurement can be used to detect superfluidity for a two-band Bose-Hubbard model coupled to a cavity field. The atom-photon coupling induces transitions between the two internal atomic levels and results in entangled polaritonic ... More
Weyl Neutrinos on a Lattice: An Explicit ConstructionSep 18 1993Oct 04 1993Introducing a new and universally applicable discretizing technique, I construct a class of local and unitary lattice theories of Weyl neutrinos; this solves a longstanding and allegedly unsolvable problem in quantum field theory. En route, I also prove ... More
Attention Monitoring and Hazard Assessment with Bio-Sensing and Vision: Empirical Analysis Utilizing CNNs on the KITTI DatasetMay 01 2019Assessing the driver's attention and detecting various hazardous and non-hazardous events during a drive are critical for driver's safety. Attention monitoring in driving scenarios has mostly been carried out using vision (camera-based) modality by tracking ... More
Transversality of smooth definable maps in O-minimal structuresNov 29 2017We present a definable smooth version of the Thom transversality theorem. We show further that the set of non-transverse definable smooth maps is nowhere dense in the definable smooth topology. Finally, we prove a definable version of a theorem of Trotman ... More
Bures distance and transition probability for $α$-CPD-kernelsMay 15 2016If the symmetry (fixed invertible self adjoint map) of Krein spaces is replaced by a fixed unitary, then we obtain the notion of S-spaces which was introduced by Szafraniec. Assume $\alpha$ to be an automorphism on a $C^*$-algebra. In this article, we ... More
Theoretical Studies of Superconductor-Insulator TransitionsSep 18 2013In this article we study superconductor-insulator transitions within the general framework of an attractive Hubbard model. This is a well-defined model of s-wave superconductivity which permits different tuning parameters (disorder and field). Furthermore, ... More
Tuning the Chern number and Berry curvature with spin-orbit coupling and magnetic texturesMar 03 2015We obtain the band structure of a particle moving in a magnetic spin texture, classified by its chirality and structure factor, in the presence of spin-orbit coupling. This rich interplay leads to a variety of novel topological phases characterized by ... More
Gauge-Mediated Supersymmetry Breaking within the Dynamical Messenger SectorJul 23 1997We consider the idea of combining the supersymmetry breaking and messenger sectors in models of gauge-mediated supersymmetry breaking. We discuss the advantages and problems of such models, and present an existence proof by constructing an explicit example. ... More
Looking at the Driver/Rider in Autonomous Vehicles to Predict Take-Over ReadinessNov 14 2018Continuous estimation the driver's take-over readiness is critical for safe and timely transfer of control during the failure modes of autonomous vehicles. In this paper, we propose a data-driven approach for estimating the driver's take-over readiness ... More
The Power of Localization for Efficiently Learning Linear Separators with NoiseJul 31 2013Jun 03 2018We introduce a new approach for designing computationally efficient learning algorithms that are tolerant to noise, and demonstrate its effectiveness by designing algorithms with improved noise tolerance guarantees for learning linear separators. We consider ... More
HandyNet: A One-stop Solution to Detect, Segment, Localize & Analyze Driver HandsApr 20 2018Jan 30 2019Tasks related to human hands have long been part of the computer vision community. Hands being the primary actuators for humans, convey a lot about activities and intents, in addition to being an alternative form of communication/interaction with other ... More
Looking at Hands in Autonomous Vehicles: A ConvNet Approach using Part Affinity FieldsApr 03 2018In the context of autonomous driving, where humans may need to take over in the event where the computer may issue a takeover request, a key step towards driving safety is the monitoring of the hands to ensure the driver is ready for such a request. This ... More
No Blind Spots: Full-Surround Multi-Object Tracking for Autonomous Vehicles using Cameras & LiDARsFeb 23 2018Feb 19 2019Online multi-object tracking (MOT) is extremely important for high-level spatial reasoning and path planning for autonomous and highly-automated vehicles. In this paper, we present a modular framework for tracking multiple objects (vehicles), capable ... More
Convolutional Social Pooling for Vehicle Trajectory PredictionMay 15 2018Forecasting the motion of surrounding vehicles is a critical ability for an autonomous vehicle deployed in complex traffic. Motion of all vehicles in a scene is governed by the traffic context, i.e., the motion and relative spatial configuration of neighboring ... More
A Non - Singular Cosmological Model with Shear and RotationDec 15 2011We have investigated a non-static and rotating model of the universe with an imperfect fluid distribution. It is found that the model is free from singularity and represents an ever expanding universe with shear and rotation vanishing for large value ... More
Fuzzy Cosets and their Gravity DualsJul 03 2000Sep 08 2000Dp-branes placed in a certain external RR (p+4)-form field expand into a transverse fuzzy two-sphere, as shown by Myers. We find that by changing the (p+4)-form background other fuzzy cosets can be obtained. Three new examples, S^2 X S^2, CP^2 and SU(3)/(U(1) ... More
An Inflationary Model in String TheoryMar 21 2004Apr 02 2004We construct a model of inflation in string theory after carefully taking into account moduli stabilization. The setting is a warped compactification of Type IIB string theory in the presence of D3 and anti-D3-branes. The inflaton is the position of a ... More
Restriction theorems for homogeneous bundlesNov 29 2004Mar 30 2005We prove that for an irreducible representation $\tau:GL(n)\to GL(W)$, the associated homogeneous ${\bf P}_k^n$-vector bundle $W_{\tau}$ is strongly semistable when restricted to any smooth quadric or to any smooth cubic in ${\bf P}_k^n$, where $k$ is ... More
Additive Approximation for Near-Perfect Phylogeny ConstructionJun 14 2012We study the problem of constructing phylogenetic trees for a given set of species. The problem is formulated as that of finding a minimum Steiner tree on $n$ points over the Boolean hypercube of dimension $d$. It is known that an optimal tree can be ... More
Strong Decays of Strange Charmed P-Wave MesonsNov 17 1993Feb 01 1994Goldstone boson decays of P-wave $D_s^{**}$ mesons are studied within the framework of Heavy Hadron Chiral Perturbation Theory. We first analyze the simplest single kaon decays of these strange charmed mesons. We derive a model independent prediction ... More
Method of Moments for computing electromagnetic scattering from a rough cylinderMay 09 2015In this tutorial paper, we formulate a two-dimensional integral-equation based method of moments approach for numerically computing the electromagnetic fields scattered from an azimuthally-rough dielectric cylinder or an axially-rough perfectly conducting ... More
Discrete Flux as Quantum HairAug 10 1999We investigate Yang-Mills theory on a spatial torus at finite temperature in the presence of discrete electric and magnetic fluxes using the AdS/CFT correspondence. We calculate the leading dependence of the partition function on the fluxes using the ... More
Information Consumption by Reissner-Nordstrom Black HolesFeb 17 1993The low-energy scattering of charged fermions by extremal magnetic Reissner-Nordstrom black holes is analyzed in the large-$N$ and $S$-wave approximations. It is shown that (in these approximations) information is carried into a causally inaccessible ... More
Multi-Modal Trajectory Prediction of Surrounding Vehicles with Maneuver based LSTMsMay 15 2018To safely and efficiently navigate through complex traffic scenarios, autonomous vehicles need to have the ability to predict the future motion of surrounding vehicles. Multiple interacting agents, the multi-modal nature of driver behavior, and the inherent ... More
On The Stability Of Non-Supersymmetric AdS VacuaFeb 24 2010May 24 2010We consider two infinite families of Non-Supersymmetric $AdS_4$ vacua, called Type 2) and Type 3) vacua, that arise in massive IIA supergravity with flux. We show that both families are perturbatively stable. We then examine non-perturbative decays of ... More
Scene Induced Multi-Modal Trajectory Forecasting via PlanningMay 23 2019We address multi-modal trajectory forecasting of agents in unknown scenes by formulating it as a planning problem. We present an approach consisting of three models; a goal prediction model to identify potential goals of the agent, an inverse reinforcement ... More
An Occluded Stacked Hourglass Approach to Facial Landmark Localization and Occlusion EstimationFeb 05 2018A key step to driver safety is to observe the driver's activities with the face being a key step in this process to extracting information such as head pose, blink rate, yawns, talking to passenger which can then help derive higher level information such ... More
Hybrid Automata for Formal Modeling and Verification of Cyber-Physical SystemsMar 17 2015The presence of a tight integration between the discrete control (the "cyber") and the analog environment (the "physical")---via sensors and actuators over wired or wireless communication networks---is the defining feature of cyber-physical systems. Hence, ... More
The Power of Localization for Efficiently Learning Linear Separators with NoiseJul 31 2013Oct 12 2016We introduce a new approach for designing computationally efficient learning algorithms that are tolerant to noise, and demonstrate its effectiveness by designing algorithms with improved noise tolerance guarantees for learning linear separators. We consider ... More
Efficient PAC Learning from the CrowdMar 21 2017Apr 13 2017In recent years crowdsourcing has become the method of choice for gathering labeled training data for learning algorithms. Standard approaches to crowdsourcing view the process of acquiring labeled data separately from the process of learning a classifier ... More
Periodically Driving a Many-Body Localized Quantum SystemJul 26 2016We experimentally study a periodically driven many-body localized system realized by interacting fermions in a one-dimensional quasi-disordered optical lattice. By preparing the system in a far-from-equilibrium state and monitoring the remains of an imprinted ... More