Results for "Dinesh Singh"

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An Analytic Perturbation Approach for Classical Spinning Particle DynamicsJun 07 2007Apr 10 2008A perturbation method to analytically describe the dynamics of a classical spinning particle, based on the Mathisson-Papapetrou-Dixon (MPD) equations of motion, is presented. By a power series expansion with respect to the particle's spin magnitude, it ... More
Perturbation Method for Classical Spinning Particle Motion: II. Vaidya Space-TimeAug 22 2008Nov 19 2008This paper describes an application of the Mathisson-Papapetrou-Dixon (MPD) equations in analytic perturbation form to the case of circular motion around a radially accreting or radiating black hole described by the Vaidya metric. Based on the formalism ... More
The Dynamics of a Classical Spinning Particle in Vaidya Space-TimeSep 13 2005Based on the Mathisson-Papapetrou-Dixon (MPD) equations and the Vaidya metric, the motion of a spinning point particle orbiting a non-rotating star while undergoing radiation-induced gravitational collapse is studied in detail. A comprehensive analysis ... More
Neutrino Helicity and Chirality Transitions in Schwarzschild Space-TimeJan 11 2004Mar 23 2005We study the helicity and chirality transitions of a high-energy neutrino propagating in a Schwarzschild space-time background. Using both traditional Schwarzschild and isotropic spherical co-ordinates, we derive an ultrarelativistic approximation of ... More
Perturbation Method for Classical Spinning Particle Motion: I. Kerr Space-TimeAug 22 2008Oct 07 2008This paper presents an analytic perturbation approach to the dynamics of a classical spinning particle, according to the Mathisson-Papapetrou-Dixon (MPD) equations of motion, with a direct application to circular motion around a Kerr black hole. The formalism ... More
Extending Beurling and De Branges to Weighted ShiftsAug 08 2016In this note we characterize all Hilbert spaces that are algebraically contained in the Hardy space $H^2$ and are also invariant under the operator of multiplication by the coordinate function $z$ whose action is assumed to be weaker than that of an isometry. ... More
Breakdown of Casimir Invariance in Curved Space-TimeFeb 03 2009May 22 2010It is shown that the commonly accepted definition for the Casimir scalar operators of the Poincare group does not satisfy the properties of Casimir invariance when applied to the non-inertial motion of elementary particles while in the presence of external ... More
Dynamics of Extended Spinning Masses in a Gravitational FieldAug 13 2006Nov 30 2006We develop a first-order approximation method for the influence of spin on the motion of extended spinning test masses in a gravitational field. This approach is illustrated for approximately circular equatorial motion in the exterior Kerr spacetime. ... More
Function Theory in Real Hardy SpacesMar 20 2008Mar 23 2008We show that many classical results in Hardy space theory have exact analogues when the Fourier coefficients are allowed only to be real.
Breakdown of Lorentz Invariance for Spin-1/2 Particle Motion in Curved Space-Time with Applications to Muon DecayJul 07 2008Mar 10 2009This paper explores the properties of the Pauli-Lubanski spin vector for the general motion of spin-1/2 particles in curved space-time. Building upon previously determined results in flat space-time, it is shown that the associated Casimir scalar for ... More
Local Space-Time Curvature Effects on Quantum Orbital Angular MomentumJan 05 2011Apr 01 2011This paper claims that local space-time curvature can non-trivially contribute to the properties of orbital angular momentum in quantum mechanics. Of key importance is the demonstration that an extended orbital angular momentum operator due to gravitation ... More
A New Perspective on Path Integral Quantum Mechanics in Curved Space-TimeAug 09 2010Jul 05 2011A fundamentally different approach to path integral quantum mechanics in curved space-time is presented, as compared to the standard approaches currently available in the literature. Within the context of scalar particle propagation in a locally curved ... More
The implications of noninertial motion on covariant quantum spinJun 19 2005Apr 06 2007It is shown that the Pauli-Lubanski spin vector defined in terms of curvilinear co-ordinates does not satisfy Lorentz invariance for spin-1/2 particles in noninertial motion along a curved trajectory. The possibility of detecting this violation in muon ... More
Lax-Halmos Type Theorems in H^p SpacesMay 20 2012Jul 31 2012In this paper we characterize for 0 < p \leq \infty, the closed subspaces of Hp that are invariant under multiplication by all powers of a finite Blaschke factor B, except the first power. Our result clearly generalizes the invariant subspace theorem ... More
Is There an Observable Limit to Lorentz Invariance at the Compton Wavelength Scale?Mar 26 2009Feb 04 2010The possibility of a frame-induced violation of Lorentz invariance due to non-inertial spin-1/2 particle motion is explored in detail for muon decay while in orbit near the event horizon of a microscopic Kerr black hole. It is explicitly shown that kinematic ... More
Effects of Space-Time Curvature on Spin-1/2 Particle ZitterbewegungMar 07 2009Aug 27 2009This paper investigates the properties of spin-1/2 particle Zitterbewegung in the presence of a general curved space-time background described in terms of Fermi normal co-ordinates, where the spatial part is expressed using general curvilinear co-ordinates. ... More
A Class of Sub-Hardy Hilbert Spaces Associated with Weighted ShiftsAug 08 2016Apr 01 2017In this note we study sub-Hardy Hilbert spaces on which the the action of the operator of multiplication by the coordinate function z is assumed to be weaker than that of an isometry. We identify such operators with a class of weighted shifts. The well ... More
A Hybrid Framework for Action Recognition in Low-Quality Video SequencesMar 11 2019Vision-based activity recognition is essential for security, monitoring and surveillance applications. Further, real-time analysis having low-quality video and contain less information about surrounding due to poor illumination, and occlusions. Therefore, ... More
Extensions of the Inequalities of Hardy and HilbertFeb 20 2015In this note we produce generalized versions of the classical inequalities of Hardy and of Hilbert and we establish their equivalence. Our methods rely on the H^1-BMOA duality. We produce a class of examples to establish that the generalizations are non-trivial. ... More
Crystallite Size Effect on Lattice Strain and Crystal Structure of Ba1/4Sr3/4MnO3 Layered Perovskite ManganiteJul 13 2018Nov 29 2018The single phase polycrystalline Ba1/4Sr3/4MnO3 layered perovskite manganite has been synthesized by combustion method having various crystallite sizes. The room temperature X-ray diffraction patterns reveal that Ba1/4Sr3/4MnO3 crystallizes into hexagonal ... More
Some result on escaping set of an entire functionSep 13 2016We study some relation between escaping sets of two permutable entire functions. In addition, we investigate the dynamical properties of the map $f(z)=z+1+e^{-z}.$
A short proof of Grinshpon's theoremApr 06 2009Grinshpon has proved that if $S$ is a commutative subring of a ring $R$ and $A\in M_n(S)$ is invertible in $M_n(R)$, then $det(A)$ is invertible in $R$. We give a very short proof of the result.
Algebraic Cobordism of Classifying SpacesJul 25 2009We define algebraic cobordism of classifying spaces, \Omega^*(BG) and G-equivariant algebraic cobordism \Omega^*_G(-) for a linear algebraic group G. We prove some properties of the coniveau filtration on algebraic cobordism, denoted F^j(\Omega^*(-)), ... More
Can Gravity Distinguish Between Dirac and Majorana Neutrinos?May 31 2006Jul 05 2006We show that spin-gravity interaction can distinguish between Dirac and Majorana neutrino wave packets propagating in a Lense-Thirring background. Using time-independent perturbation theory and gravitational phase to generate a perturbation Hamiltonian ... More
A Finite Multiplicity Helson-Lowdenslager-De Branges TheoremOct 28 2009This paper proves two theorems. The first of these simplifies and lends clarity to the previous characterizations of the invariant subspaces of $S$, the operator of multiplication by the coordinate function $z$, on $L^2(\mathbb{T};\mathbb{C}^n)$, where ... More
Signatures of Noncommutative Geometry in Muon Decay for Nonsymmetric GravityJan 27 2009It is shown how to identify potential signatures of noncommutative geometry within the decay spectrum of a muon in orbit near the event horizon of a microscopic Schwarzschild black hole. This possibility follows from a re-interpretation of J.W. Moffat's ... More
Spin dynamics of a millisecond pulsar orbiting closely around a massive black holeFeb 08 2019We investigate the spin dynamics of a millisecond pulsar (MSP) in a tightly bounded orbit around a massive black hole. These binaries are progenitors of the extreme-mass-ratio-inspirals (EMRIs) and intermediate-mass-ratio-inspirals (IMRIs) gravitational ... More
Sub-Hardy Hilbert spaces on the circle and torusOct 24 2013Sahni and Singh settled a problem posed by Yousefi & Hesameddini by generalizing their main result with a simple proof in the setting of sub-Hilbert spaces in $H^2(T)$. In this paper, we extend the main result of Sahni and Singh to the setting of the ... More
Tidal Dynamics in Cosmological SpacetimesMay 09 2007Jun 19 2010We study the relative motion of nearby free test particles in cosmological spacetimes, such as the FLRW and LTB models. In particular, the influence of spatial inhomogeneities on local tidal accelerations is investigated. The implications of our results ... More
Helicity Precession of Spin-1/2 Particles in Weak Inertial and Gravitational FieldsMay 30 2004We calculate the helicity and chirality effects experienced by a spin-1/2 particle subjected to classical electromagnetic and gravitational fields. The helicity evolution is then determined in the non-relativistic, relativistic, and ultra-relativistic ... More
Fast Spinning Pulsars as Probes of Massive Black Holes' GravityMar 27 2014Dwarf galaxies and globular clusters may contain intermediate mass black holes ($10^{3}$ to $10^{5}$ solar masses) in their cores. Estimates of ~$10^{3}$ neutron stars in the central parsec of the Galaxy and similar numbers in small elliptical galaxies ... More
Reply to Comment on ``Can gravity distinguish between Dirac and Majorana neutrinos?''Nov 03 2006This is a reply to a comment (gr-qc/0610098) written by Nieves and Pal about our paper (gr-qc/0605153) published in Phys. Rev. Lett. 97, 041101 (2006).
The Distinction Between Dirac and Majorana Neutrino Wave Packets Due to Gravity and Its Impact on Neutrino OscillationsJun 30 2006We present the possibility that Dirac and Majorana neutrino wave packets can be distinguished when subject to spin-gravity interaction while propagating through vacuum described by the Lense-Thirring metric. By adopting the techniques of gravitational ... More
Escaping Set of e^z-1May 27 2012Jun 12 2012We investigate the set I(f) of points that converge to infinity under iteration of the map f(z) = e^z-1 and show that it is the disjoint union of countably many rays and uncountable union of infinite sets whose points escape to infinity through the sets. ... More
Invariance Under Bounded Analytic FunctionsFeb 18 2016In a recent paper, M. Raghupathi has extended the famous theorem of Beurling to the context of subspaces that are invariant under the class of subalgebras of $H^\infty$ of the form $IH^\infty$, where $I$ is an inner function. In this paper, we provide ... More
Neutrino Wave Packet Propagation in Gravitational FieldsFeb 23 2005May 12 2005We discuss the propagation of neutrino wave packets in a Lense-Thirring space-time using a gravitational phase approach. We show that the neutrino oscillation length is altered by gravitational corrections and that neutrinos are subject to helicity flip ... More
Synthesis, Structural and Optical Properties of (ALa)(FeMn)O6 (A = Ba and Sr) Double PerovskitesMar 04 2019Here, we report structural and optical properties of (ALa)(FeMn)O6 (A = Ba and Sr) double perovskite synthesized via auto-combustion followed by a calcination process. Rietveld refinement of the structure using x-ray diffraction data reveals that (BaLa)(FeMn)O6 ... More
Linear Stability Invariant Metapopulations Network PartitioningApr 22 2019Metapopulations is a multi-patch habitat system, where populations live and interact in habitat patches, and individuals disperse from one patch to other via dispersal connections. The loss of dispersal connections among habitat patches can impact negatively ... More
A Constrained Nevanlinna-Pick Interpolation ProblemNov 13 2007We obtain necessary and sufficient conditions for Nevanlinna-Pick interpolation on the unit disk with the additional restriction that all analytic interpolating functions satisfy $f'(0)=0.$ Alternatively, these results can be interpreted as interpolation ... More
X-ray Diffraction Analysis of Cu2+ Doped Zn1-xCuxFe2O4 Spinel Nanoparticles using Williamson-Hall Plot MethodNov 30 2018Feb 05 2019The nanoparticles (NPs) of Zn1-xCuxFe2O4 (ZCFO) spinels with x = 0, 0.2, 0.4, 0.6 and 0.8 were synthesized by a sol-gel combustion method using acetate precursor. The NPs of ZCFO were prepared by following calcination process at 600C for 8hrs. The synthesized ... More
Medium Modification of Charm Production in Relativistic Heavy Ion Collisions due to Pre-equilibrium Dynamics of Partons at $\sqrt{s_{\textrm {NN}}}$= 0.2--5.02 TeVApr 18 2019We study the production dynamics of charm quarks in the parton cascade model for relativistic heavy ion collisions at RHIC and LHC energies. The model is eminently suited for a study of the pre-equilibrium dynamics of charm quarks at modest transverse ... More
Characterizing driving behavior using automatic visual analysisMar 13 2015In this work, we present the problem of rash driving detection algorithm using a single wide angle camera sensor, particularly useful in the Indian context. To our knowledge this rash driving problem has not been addressed using Image processing techniques ... More
Vehicle Local Position Estimation SystemMar 23 2015In this paper, a robust vehicle local position estimation with the help of single camera sensor and GPS is presented. A modified Inverse Perspective Mapping, illuminant Invariant techniques and object detection based approach is used to localize the vehicle ... More
Efficient Probabilistic Collision Detection for Non-Convex ShapesOct 12 2016We present new algorithms to perform fast probabilistic collision queries between convex as well as non-convex objects. Our approach is applicable to general shapes, where one or more objects are represented using Gaussian probability distributions. We ... More
Ab initio molecular dynamics via density based energy functionalsJul 08 1994The use of energy functionals based on density as the basic variable is advocated for ab initio molecular dynamics. It is demonstrated that the constraint of positivity of density can be incorporated easily by using square root density for minimization ... More
Reduced order multi switching hybrid synchronization of chaotic systemsApr 09 2018In this article, a new synchronization scheme is presented by combining the concept of reduced-order synchronization with multi-switching synchronization schemes. The presented scheme, reduced-order multi-switching hybrid synchronization, is notable addition ... More
Chance constraint based multi agent navigation under uncertaintyAug 20 2016We present Probabilistic Reciprocal Velocity Obstacle or PRVO as a general algorithm for navigating multiple robots under perception and motion uncertainty. PRVO is defined as the space of velocities that ensures dynamic collision avoidance between a ... More
Comparison of secure and high capacity color image steganography techniques in RGB and YCbCr domainsJul 11 2013Steganography is one of the methods used for secret communication. Steganography attempts to hide the existence of the information. The object used to hide the secret information is called as cover object. Images are the most popular cover objects used ... More
Statistical Theory of Force Induced Unzipping of DNAMay 07 2004May 18 2005The unzipping transition under the influence of external force of a dsDNA molecule has been studied using the Peyrard-Bishop Hamiltonian. The critical force $F_c(T)$ is found to depend on the potential parameters $k$, represents the stiffness of single ... More
Effect of defects on thermal denaturation of DNA OligomersMay 03 2001Aug 29 2001The effect of defects on the melting profile of short heterogeneous DNA chains are calculated using the Peyrard-Bishop Hamiltonian. The on-site potential on a defect site is represented by a potential which has only the short-range repulsion and the flat ... More
Earthquake Disaster based Efficient Resource Utilization Technique in IaaS CloudJun 27 2013Jan 27 2014Cloud Computing is an emerging area. The main aim of the initial search-and-rescue period after strong earthquakes is to reduce the whole number of mortalities. One main trouble rising in this period is to and the greatest assignment of available resources ... More
Case Study Based Software Engineering Project Development: State of ArtJun 11 2013This research paper designates the importance and usage of the case study approach effectively to educating and training software designers and software engineers both in academic and industry. Subsequently an account of the use of case studies based ... More
Microcontroller Based Testing of Digital IP-CoreMay 09 2012Testing core based System on Chip is a challenge for the test engineers. To test the complete SOC at one time with maximum fault coverage, test engineers prefer to test each IP-core separately. At speed testing using external testers is more expensive ... More
Effect of genome sequence on the force-induced unzipping of a DNA moleculeMar 14 2006We considered a dsDNA polymer in which distribution of bases are random at the base pair level but ordered at a length of 18 base pairs and calculated its force elongation behaviour in the constant extension ensemble. The unzipping force $F(y)$ vs. extension ... More
Statistical Mechanics of thermal denaturation of DNA oligomersMay 07 2004Double stranded DNA chain is known to have nontrivial elasticity. We study the effect of this elasticity on the denaturation profile of DNA oligomer by constraining one base pair at one end of the oligomer to remain in unstretched (or intact) state. The ... More
It's a dark, dark world: Background evolution of interacting $φ$CDM models beyond simple exponential potentialsJul 06 2015May 06 2016We study the background cosmological dynamics with a three component source content: a radiation fluid, a barotropic fluid to mimic the matter sector and a single scalar field which can act as dark energy giving rise to the late-time accelerated phase. ... More
A Text to Speech (TTS) System with English to Punjabi ConversionNov 13 2014The paper aims to show how an application can be developed that converts the English language into the Punjabi Language, and the same application can convert the Text to Speech(TTS) i.e. pronounce the text. This application can be really beneficial for ... More
Pulling short DNA molecules having defects on different locationsSep 28 2015We present a study on the role of defects on the stability of short DNA molecules. We consider short DNA molecules (16 base pairs) and investigate the thermal as well as mechanical denaturation of these molecules in the presence of defects that occurs ... More
Reusability Framework for Cloud ComputingOct 30 2012Cloud based development is a challenging task for several software engineering projects, especially for those which needs development with reusability. Present time of cloud computing is allowing new professional models for using the software development. ... More
Design and Implementation of Bit Transition CounterFeb 11 2014In today VLSI system design, power consumption is gaining more attention as compared to performance and area. This is due to battery life in portable devices and operating frequency of the design. Power consumption mainly consists of static power, dynamic ... More
Phase diagram of mechanically stretched DNA: The salt effectSep 05 2014The cations, in form of salt, present in the solution containing DNA play a crucial role in the opening of two strands of DNA. We use a simple non linear model and investigate the role of these cations on the mechanical unzipping of DNA. The Hamiltonian ... More
Effect of salt concentration on the stability of heterogeneous DNASep 28 2015We study the role of cations on the stability of double stranded DNA (dsDNA) molecules.It is known that the two strands of double stranded DNA(dsDNA) have negative charge due to phosphate group. Cations in the form of salt in the solution, act as shielding ... More
Unbiased Ratio-Type Estimator Using Transformed Auxiliary Variable In Negative Correlation CaseOct 06 2012The objective of this paper is to propose an unbiased ratio-type estimator for finite population mean when the variables are negatively correlated. Hartley and Ross[2] and Singh and Singh [6] estimators are identified as particular cases of the proposed ... More
Substrate Mediated Synthesis of Ti-Si-N Nano-and-Micro Structures for Optoelectronic ApplicationsMar 29 2019Being one of the strongest materials, ternary TiSiN exhibits a very interesting family of binary transition metal nitride and silicide systems. A novel technique to fabricate morphologically fascinating nano and micro structures of TiSiN is reported here. ... More
Preliminary Studies on Force/Motion Control of Intelligent Mechanical SystemsFeb 22 2014To rationalize the relatively high investment that industrial automation systems entail, research in the field of intelligent machines should target high value functions such as fettling, die-finishing, deburring, and fixtureless manufacturing. For achieving ... More
A New Similarity Measure for Taxonomy Based on Edge CountingNov 20 2012This paper introduces a new similarity measure based on edge counting in a taxonomy like WorldNet or Ontology. Measurement of similarity between text segments or concepts is very useful for many applications like information retrieval, ontology matching, ... More
Reduced Dimensionality tailored HN(C)N Pulse Sequences for Efficient Backbone Resonance Assignment of Proteins through Rapid Identification of Sequential HSQC peaksMay 21 2013Two novel reduced dimensionality (RD) experiments -(4,3)D-hNCOcaNH and (4,3)D-hNcoCANH- have been presented here to facilitate the backbone resonance assignment of proteins both in terms of its accuracy and speed. The experiments basically represent an ... More
On dynamics of semiconjugated entire functionsAug 11 2013May 18 2014Let $g$ and $h$ be transcendental entire functions and let $f$ be a continuous map of the complex plane into itself with $f\circ g=h\circ f.$ Then $g$ and $h$ are said to be semiconjugated by $f$ and $f$ is called a semiconjugacy. We consider the dynamical ... More
Unit-Regularity of Regular Nilpotent ElementsSep 26 2015Dec 23 2015Let $a$ be a regular element of a ring $R$. If either $K:=\rm{r}_R(a)$ has the exchange property or every power of $a$ is regular, then we prove that for every positive integer $n$ there exist decompositions $$ R_R = K \oplus X_n \oplus Y_n = E_n \oplus ... More
Dilations, Wandering Subspaces, and Inner FunctionsSep 23 2015The object of this paper is to study wandering subspaces for commuting tuples of operators on Hilbert spaces. It is shown that, for a large class of analytic functional Hilbert spaces on the unit ball, wandering subspaces for restrictions of the multiplication ... More
Network Formation Game with Different Cost Value for PlayersApr 12 2016In Social Networks, it is often interesting to study type of networks formed, its efficiency with respect to social objective and which networks are stable. Many work have already been there in this area. Players in network formation game will incur some ... More
Reduced Dimensionality (4,3)D-hnCOCANH Experiment: An Efficient Backbone Assignment tool for NMR studies of ProteinsFeb 18 2013Sequence specific resonance assignment and secondary structure determination of proteins form the basis for variety of structural and functional proteomics studies by NMR. In this context, an efficient standalone method for rapid assignment of backbone ... More
The Cohomology Ring of the Space of Rational FunctionsJul 25 2009Let Rat_k be the space of based holomorphic maps from S^2 to itself of degree k. Let beta_k denote the Artin's braid group on k strings and let Bbeta_k be the classifying space of beta_k. Let C_k denote the space of configurations of length less than ... More
Exemplar-AMMs: Recognizing Crowd Movements from Pedestrian TrajectoriesMar 31 2016In this paper, we present a novel method to recognize the types of crowd movement from crowd trajectories using agent-based motion models (AMMs). Our idea is to apply a number of AMMs, referred to as exemplar-AMMs, to describe the crowd movement. Specifically, ... More
Nuclear Environments Inspection with Micro Aerial Vehicles: Algorithms and ExperimentsMar 14 2019In this work, we address the estimation, planning, control and mapping problems to allow a small quadrotor to autonomously inspect the interior of hazardous damaged nuclear sites. These algorithms run onboard on a computationally limited CPU. We investigate ... More
D* polarization as a probe to discriminate new physics in B --> D* tau nubarJun 10 2016The confirmation of excess in R_{D*} at the LHCb is an indication of lepton flavor non-universality. In order to identify the Lorentz structure of new physics responsible for this excess, one requires measurements of angular observables in B --> D* tau ... More
SocioSense: Robot Navigation Amongst Pedestrians with Social and Psychological ConstraintsJun 04 2017We present a real-time algorithm, SocioSense, for socially-aware navigation of a robot amongst pedestrians. Our approach computes time-varying behaviors of each pedestrian using Bayesian learning and Personality Trait theory. These psychological characteristics ... More
Secured Data Consistency and Storage Way in Untrusted Cloud using Server Management AlgorithmNov 10 2011It is very challenging part to keep safely all required data that are needed in many applications for user in cloud. Storing our data in cloud may not be fully trustworthy. Since client doesn't have copy of all stored data, he has to depend on Cloud Service ... More
High Quality Requirement Engineering and Applying Priority Based Tools for QoS Standardization in Web Service ArchitectureMar 24 2013Even though there are more development to improving the Quality of Service and requirement engineering in web services yet there is a big scarcity for its related standardization in day to day progress leading to vast needs in its area. Also in web service ... More
Students' conceptual knowledge of energy and momentumFeb 25 2016We investigate student understanding of energy and momentum concepts at the level of introductory physics by designing and administering a 25-item multiple choice test and conducting individual interviews. We find that most students have difficulty in ... More
Assessing Student Expertise in Introductory Physics with Isomorphic Problems, Part I: Performance on Non-intuitive Problem Pair from Introductory PhysicsFeb 21 2016Investigations related to expertise in problem solving and ability to transfer learning from one context to another are important for developing strategies to help students perform more expert-like tasks. Here we analyze written responses to a pair of ... More
Problem Solving and LearningFeb 20 2016One finding of cognitive research is that people do not automatically acquire usable knowledge by spending lots of time on task. Because students' knowledge hierarchy is more fragmented, "knowledge chunks" are smaller than those of experts. The limited ... More
Effectiveness of group interaction on conceptual standardized test performanceJul 25 2002Jul 26 2002We analyze the effectiveness of working in pairs on the Conceptual Survey of Electricity and Magnetism test in a calculus-based introductory physics course. The group performance shows large normalized gain and evidence for co-construction. We discuss ... More
Vertex-disjoint Cycle Cover for graph signal processingFeb 19 2016Eigenvectors of the Laplacian of a cycle graph exhibit the sinusoidal characteristics of the standard DFT basis, and signals defined on such graphs are amenable to linear shift invariant (LSI) operations. In this paper we propose to reduce a generic graph ... More
Interactive learning tutorials on quantum mechanicsMar 10 2016We discuss the development and evaluation of quantum interactive learning tutorials (QuILTs) which are suitable for undergraduate courses in quantum mechanics. QuILTs are based on the investigation of student difficulties in learning quantum physics. ... More
Bohm's realist interpretation of Quantum mechanicsMay 13 2008A brief account of the world view of classical physics is given first. We then recapitulate as to why the Copenhagen interpretation of the quantum mechanics had to renounce most of the attractive features of the clasical world view such as a causal description, ... More
Hidden Variables, Non Contextuality and Einstein-Locality in Quantum MechanicsJul 19 2005Jul 25 2005We discuss the problem of hidden variables and the motivation for introducting them in quantum mechanics. These include determinism, and the problem of meassurement and incompleteness. We first discuss Von-Neumann's imposisbility proof and then analyse ... More
The Yang-Mills and chiral fields in six dimensionsNov 14 2012Feb 20 2013In previous work (Singh, 2011), we constructed an action in six dimensions using Yang-Mills fields and an auxiliary Abelian field. Here we first write down all the equations of motion and the constraints which arise from such an action. From these equations ... More
Super-Yang-Mills and M5-branesJul 18 2011Aug 23 2011We uplift 5-dimensional super-Yang-Mills theory to a 6-dimensional gauge theory with the help of a space-like constant vector $\eta^M$, whose norm determines the Yang-Mills coupling constant. After the localization of $\eta^M$ the 6D gauge theory acquires ... More
New Supersymmetric Vacua for N=4, D=4 Gauged SupergravityJan 08 1998May 26 1998In this paper we obtain supersymmetric brane-like configurations in the vacuum of N=4 gauged $SU(2)\times SU(2)$ supergravity theory in four spacetime dimensions. Almost all of these vacuum solutions preserve either half or one quarter of the supersymmetry ... More
Macroscopic String-like Solutions in Massive SupergravityOct 24 1997Nov 25 1997In this report we obtain explicit string-like solutions of equations of motion of massive heterotic supergravity recently obtained by Bergshoeff, Roo and Eyras. We also find consistent string source which can be embedded in these backgrounds when space-time ... More
SU(N) membrane $B\wedge F$ theory with dual-pairsNov 11 2008Dec 04 2008We construct a SU(N) membrane $B\wedge F$ theory with dual pairs of scalar and tensor fields. The moduli space of the theory is precisely that of $N$ M2-branes on the noncompact flat space. The theory possesses explicit SO(8) invariance and is an extension ... More
3-Branes on Eguchi-Hanson 6D InstantonsJan 15 2007Apr 27 2007We use the approach used by Eguchi-Hanson in constructing four-dimensional instanton metrics and construct a class of regular six-dimensional instantons which are nothing but $S^2\times S^2$ resolved conifolds. We then also obtain D3-brane solutions on ... More
Generalised Penrose Limits and PP-WavesJul 09 2003Jan 31 2004In this paper we construct generalised Penrose limits for the solutions of massive type IIA supergravity. We consider a Freund-Rubin type solution and apply these {\it massive} Penrose limits and obtain supersymmetric pp-wave which is a standard type ... More
Magnetic Wormholes and Vertex OperatorsJul 20 1994We consider wormhole solutions in $2+1$ Euclidean dimensions. A duality transformation is introduced to derive a new action from magnetic wormhole action of Gupta, Hughes, Preskill and Wise. The classical solution is presented. The vertex operators corresponding ... More
Proposal for designing a two-stage buffer gas cooled beam sourceJan 11 2019A novel two-stage helium buffer gas cooled beam source is introduced. The properties of the molecular beams produced from this source are investigated theoretically using the CaF as a test molecule. The gas phase molecules are first produced inside a ... More
Quantum Stern-Gerlach experiment and path entanglement of Bose-Einstein condensateAug 14 2016In this paper, a quantum Stern-Gerlach thought experiment is introduced where, in addition to the intrinsic angular momentum of an atom, the magnetic field is also treated quantum mechanically. A freely falling spin polarised Bose-Einstein condensate ... More
On the failure of mean-field theories near a critical pointFeb 27 2014Mar 04 2014It is well known that mean-field theories fail to reproduce the experimentally known critical exponents. The traditional argument which explain this failure of mean-field theories near a critical point is the Ginsburg criterion in which diverging fluctuations ... More
Thermodynamical Phase transitions, the mean-field theories, and the renormalization (semi)group: A pedagogical introductionFeb 27 2014While analyzing second order thermodynamical phase transitions, Lev Landau (the famous Russian physicist) introduced a very vital concept, the concept of an "order parameter". This not only amalgamated the previous fragmentary theoretical understanding ... More
Prospects for the Mass Ordering (MO) and $θ_{23}$-Octant sensitivity in LBL experiments: UNO, DUNE \& NO$ν$AJun 19 2017This article represents quantitative numerical analysis to find the sensitivity for the mass ordering and octant of atmospheric mixing angle $\theta_{23}$ within 3$\sigma$ range of oscillation parameters, in the context of three long base line (LBL) accelerator ... More