Open Access. Powered by Scholars. Published by Universities.®

Physics Commons

Open Access. Powered by Scholars. Published by Universities.®

PDF

City University of New York (CUNY)

Publications and Research

Series

Discipline
Keyword
Publication Year

Articles 241 - 270 of 274

Full-Text Articles in Physics

On The Casimir Interaction Between Holes In A Plate, Daniel N. Kabat, Dimitra Karabali, V P. Nair Jan 2010

On The Casimir Interaction Between Holes In A Plate, Daniel N. Kabat, Dimitra Karabali, V P. Nair

Publications and Research

We study the leading long-distance attractive force between two holes in a plate arising from a scalar eld with Dirichlet boundary conditions on the plate. We use a formalism in which the interaction is governed by a non-local eld theory which lives on the two holes. The interaction energy is proportional to Q1Q2=r7 at large separation r, where Q1 and Q2 are certain charges associated with the holes. We compute these charges for round and rectangular holes. We show that the 1=r7 behavior is universal for separations large compared to the linear dimensions of the holes, irrespective of the spin …


The Hamiltonian Approach To Yang-Mills (2 + 1): Expansion Scheme And Corrections To String Tension, Dimitra Karabali, V P. Nair, Alexandr Yelinkov Jan 2010

The Hamiltonian Approach To Yang-Mills (2 + 1): Expansion Scheme And Corrections To String Tension, Dimitra Karabali, V P. Nair, Alexandr Yelinkov

Publications and Research

We carry out further analysis of the Hamiltonian approach to Yang-Mills theory in 2+1 dimensions which helps to place the calculation of the vacuum wave function and the string tension in the context of a systematic expansion scheme. The solution of the Schrodinger equation is carried out recursively. The computation of correlators is re-expressed in terms of a two-dimensional chiral boson theory. The effective action for this theory is calculated to first order in our expansion scheme and to the fourth order in a kinematic expansion parameter. The resulting corrections to the string tension are shown to be very small, …


Quantum Computing: Selected Internet Resources For Librarians, Researchers, And The Casually Curious, Jill Cirasella Apr 2009

Quantum Computing: Selected Internet Resources For Librarians, Researchers, And The Casually Curious, Jill Cirasella

Publications and Research

This article is an annotated selection of the most important and informative Internet resources for learning about quantum computing, finding quantum computing literature, and tracking quantum computing news.


Keeping Abreast Of Quantum News: Quantum Computing On The Web And In The Literature, Jill Cirasella Aug 2008

Keeping Abreast Of Quantum News: Quantum Computing On The Web And In The Literature, Jill Cirasella

Publications and Research

This appendix describes tools that can help you track developments in quantum computing.


Historical Bibliography Of Quantum Computing, Jill Cirasella Aug 2008

Historical Bibliography Of Quantum Computing, Jill Cirasella

Publications and Research

This bibliographic essay reviews seminal papers in quantum computing. Although quantum computing is a young science, its researchers have already published thousands of noteworthy articles, far too many to list here. Therefore, this appendix is not a comprehensive chronicle of the emergence and evolution of the field but rather a guided tour of some of the papers that spurred, formalized, and furthered its study.


Vortices And Chaos In The Quantum Fluid, D. A. Wisniacki, E. R. Pujals, F. Borondo Jan 2007

Vortices And Chaos In The Quantum Fluid, D. A. Wisniacki, E. R. Pujals, F. Borondo

Publications and Research

The motion of a single vortex originates chaos in the quantum fluid defined in Bohm's interpretation of quantum mechanics. Here we analize this situation in a very simple case: one single vortex in a rectangular billiard.


Applications Of Discoveries Range From Leveling Rice Fields To Anti-Terrorism Defenses, Aldemaro Romero Jr., Susan D. Allen Jan 2005

Applications Of Discoveries Range From Leveling Rice Fields To Anti-Terrorism Defenses, Aldemaro Romero Jr., Susan D. Allen

Publications and Research

No abstract provided.


Study Of Deconfinement In Na50, Paula Bordalo, M. C. Abreu, B. Alessandro, C. Alexa, R. Arnaldi, M. Atayan, C. Baglin, A. Baldit, M. Bedidian, S. Boelè, V. Boldea, Samuel Borenstein, C. Borges, A. Bussière, L. Capelli, C. Castagner, J. Castor, B. Chaurand, E. Chiavassa, C. Cicalò, T. Claudino, M. P. Comets, N. Constans, S. Constantinescu, P. Cortese, J. Cruz, A. De Falco, G. Dellacasa, N. De Marco, A. Devaux, S. Dita, O. Drapier, B. Espagnon, J. Fargeix, P. Force, M. Gallio, Y. K. Gavrilov, C. Gerschel, P. Giubellino, M. B. Golubeva, M. Gonin, A. A. Grigorian, J. Y. Grossiord, F. F. Guber, A. Guichard, H. Gulkanyan, R. Hakobyan, R. Haroutunian, M. Idzik, D. Jouan, T. L. Karavitcheva, L. Kluberg, A. B. Kurepin, Y Le Bornec, C. Lourenço, P. Macciotta, M. Mac Cormick, A. Marzari-Chiesa, M. Masera, A. Masoni, M. Monteno, M. Musso, P. Petiau, A. Piccotti, J. R. Pizzi, W. Prado Da Silva, F. Prino, G. Puddu, C. Quintans, L. Ramello, Laboratory Of Instrumentation And Experimental Particle Physics, L. Riccati, A. Romana, P. Saturnini, H. Santos, E. Scalas, E. Scomparin, S. Serci, R. Shahoyan, F. Sigaudo, S. Silva, M. Sitta, P. Sonderegger, X. Tarrago, N. S. Topilskaya, G. L. Usai, E. Vercellin, L. Villatte, N. Willis Apr 2003

Study Of Deconfinement In Na50, Paula Bordalo, M. C. Abreu, B. Alessandro, C. Alexa, R. Arnaldi, M. Atayan, C. Baglin, A. Baldit, M. Bedidian, S. Boelè, V. Boldea, Samuel Borenstein, C. Borges, A. Bussière, L. Capelli, C. Castagner, J. Castor, B. Chaurand, E. Chiavassa, C. Cicalò, T. Claudino, M. P. Comets, N. Constans, S. Constantinescu, P. Cortese, J. Cruz, A. De Falco, G. Dellacasa, N. De Marco, A. Devaux, S. Dita, O. Drapier, B. Espagnon, J. Fargeix, P. Force, M. Gallio, Y. K. Gavrilov, C. Gerschel, P. Giubellino, M. B. Golubeva, M. Gonin, A. A. Grigorian, J. Y. Grossiord, F. F. Guber, A. Guichard, H. Gulkanyan, R. Hakobyan, R. Haroutunian, M. Idzik, D. Jouan, T. L. Karavitcheva, L. Kluberg, A. B. Kurepin, Y Le Bornec, C. Lourenço, P. Macciotta, M. Mac Cormick, A. Marzari-Chiesa, M. Masera, A. Masoni, M. Monteno, M. Musso, P. Petiau, A. Piccotti, J. R. Pizzi, W. Prado Da Silva, F. Prino, G. Puddu, C. Quintans, L. Ramello, Laboratory Of Instrumentation And Experimental Particle Physics, L. Riccati, A. Romana, P. Saturnini, H. Santos, E. Scalas, E. Scomparin, S. Serci, R. Shahoyan, F. Sigaudo, S. Silva, M. Sitta, P. Sonderegger, X. Tarrago, N. S. Topilskaya, G. L. Usai, E. Vercellin, L. Villatte, N. Willis

Publications and Research

The J/Ψ production in 158 A Ge V Pb-Pb interactions is studied, in the dimuon decay channel, as a function of centrality, as measured with the electromagnetic or, alternatively, with the very forward hadronic calorimeters. After a first sharp variation at mid-centrality, both patterns continue to fall down and exhibit a curvature change at high centrality values. This trend excludes any conventional hadronic model and finds a natural explanation in a deconfined quark-gluon phase scenario.


Kähler-Chern-Simons Theory And Symmetries Of Anti-Self-Dual Gauge Fields, V. Parameswaran Nair, Jeremy Schiff May 1991

Kähler-Chern-Simons Theory And Symmetries Of Anti-Self-Dual Gauge Fields, V. Parameswaran Nair, Jeremy Schiff

Publications and Research

Kähler-Chern-Simons theory, which was proposed as a generalization of ordinary Chern-Simons theory, is explored in more detail. The theory describes anti-self-dual in-stantons on a four-dimensional Kähler manifold. The phase space is the space of gauge potentials, whose symplectic reduction by the constraints of anti-self-duality leads to the moduli space of instantons. We show that infinitesimal Bäcklund transformations, previously related to "hidden symmetries" of instantons, are canonical transformations generated by the anti-self-duality constraints. The quantum wave functions naturally lead to a generalized Wess-Zumino-Witten action, which in turn has associated chiral current algebras. The dimensional reduction of the anti-self-duality equations leading to …


Relativistic Wave Equation For Anyons, R. Jackiw, V. Parameswaran Nair Mar 1991

Relativistic Wave Equation For Anyons, R. Jackiw, V. Parameswaran Nair

Publications and Research

Construction of one-particle states as unitary representations of the Poincare algebra in 2 + 1 dimensions shows that an anyon has one polarization state. However, for nonzero spin manifestly linear and covariant realizations of Lorentz transformations require more than one field component, and an infinite number is needed when the value of spin is not an integer or half-integer. We discuss the relation between these two aspects of Poincare symmetry. In particular, we construct a relativistic equation for anyons where the number of physical polarizations is reduced to one by virtue of a gauge symmetry or equivalent constraint.


A Kähler-Chern-Simons Theory And Quantization Of Instanton Moduli Spaces, V. P. Nair, Jeremy Schiff Mar 1990

A Kähler-Chern-Simons Theory And Quantization Of Instanton Moduli Spaces, V. P. Nair, Jeremy Schiff

Publications and Research

A five dimensional field theory is introduced which is an analogue of three dimensional Chern-Simons theory. The reduced phase space in the theory is a moduli phase of instantons in four dimensional Euclidean gauge theory, with a symplectic structure induced by the Donaldson u-map. Issues related to quantization are discussed.


Topological Gauge Theory And Twistors, V. Parameswaran Nair, Jeremy Schiff Jul 1989

Topological Gauge Theory And Twistors, V. Parameswaran Nair, Jeremy Schiff

Publications and Research

By use of harmonic superfields, Witten’s topological gauge theory is written as a field theory on a supertwistor space. Further, using the realisation of complex compactified Minkowski space as a quadric in CP5, we show that the theory has a simple formulation in terms of analytic superfields on super-CP5 × CP3 .


U(1) Chern-Simons Theory And C=1 Conformal Blocks, Michiel Bos, V. Parameswaran Nair Jun 1989

U(1) Chern-Simons Theory And C=1 Conformal Blocks, Michiel Bos, V. Parameswaran Nair

Publications and Research

The quantization of the U ( 1 ) Chern-Simons action in three dimensions is carried out in a coherent state representation. The wave functionals obtained are generating functionals for the current correlator blocks of two-dimensional c= 1 rational conformal field theories, explicitly realizing a connection found by Witten.


A Current Algebra For Some Gauge Theory Amplitudes, V. Parameswaran Nair Nov 1988

A Current Algebra For Some Gauge Theory Amplitudes, V. Parameswaran Nair

Publications and Research

The classical amplitude for scattering of two positive helicity and n-2 negative helicity (or the other way) gauge bosons is shown to be generated by a Wess-Zumino-Witten (WZW) model for N= 4 supersymmetric gauge theory; i.e. the current algebra of the WZW model (with central charge k= 1 ) gives a Kac-Moody algebra as the symmetry behind these amplitudes.


Multi Gluon Scattering: A String Based Calculation, David Kosower, Bum-Hoon Lee, V. Parameswaran Nair Jan 1988

Multi Gluon Scattering: A String Based Calculation, David Kosower, Bum-Hoon Lee, V. Parameswaran Nair

Publications and Research

We suggest the use of open bosonic string theory to compute multigluon scattering in QCD, since gauge invariance ,cyclic symmetry etc. are manifest in this approach. The method is illustrated by the computation of five gluon scattering.


Compactification Of The Twisted Heterotic String, V. Parameswaran Nair, Alfred Shapere, Andrew Strominger, Frank Wilczek Jan 1987

Compactification Of The Twisted Heterotic String, V. Parameswaran Nair, Alfred Shapere, Andrew Strominger, Frank Wilczek

Publications and Research

We consider compactifications of the recently discovered tachyon free non-supersymmetric string on tori of Lorentzian self dual lattices. The one loop cosmological constant is computed as a function of the parameters characterizing the lattices. When the lattice parameters are treated as dynamical variables, their equations of motion require extremization of A. This extremization determines the allowed gauge groups and mass spectra. We explicitly find some extremes of A, valid to all orders in perturbation theory. A very general duality relation between compactifications is demonstrated, which leads to an equivalence of compactifications on tori of radii R aud 1/R.


General Results On Glueball Masses In Qcd, I. J. Muzinich, V. Parameswaran Nair Sep 1986

General Results On Glueball Masses In Qcd, I. J. Muzinich, V. Parameswaran Nair

Publications and Research

A number of authors have investigated mass inequalities for mesons and baryons in QCD. These provide rigorous nonperturbative constraints on the mass spectrum. Similar inequalities for glueballs are investigated. For nonzero spin J, in the large-Nc approximation, mJ - ⩾ mJ+ is found. (For J = 0, the existence of a gluon condensate can modify this statement.) There are also constraints on how fast mJ can grow with J. For example, for mJ = a + bJα, 0 ⩽ α ⩽ 1 is found, a result consistent with Regge behaviour.


Qcd Vacuum As A Chromomagnetic Superconductor: Microscopic Physics, V. Parameswaran Nair, C. Rosenzweig Jan 1985

Qcd Vacuum As A Chromomagnetic Superconductor: Microscopic Physics, V. Parameswaran Nair, C. Rosenzweig

Publications and Research

The compactness of the QCD gauge group leads to the existence of chromomagnetic monopole configurations. The interactions of these monopoles are studied using electric-magnetic duality as a guide. It is shown that the gluon-monopole interaction acquires an extra minus sign which tends to destabilize the monopole configurations. A model is presented which exploits this observation. We present a scenario where the monopoles condense, giving chromomagnetic superconductivity, via a first-order phase transition at a scale where the electric and magnetic charges are equal, i.e., α = 1/2 . In this vacuum medium gluons propagate like 1/k4 which is now seen …


(Super)Conformal Symmetry Breaking, Andrew Strominger, V. Parameswaran Nair Dec 1984

(Super)Conformal Symmetry Breaking, Andrew Strominger, V. Parameswaran Nair

Publications and Research

We argue that the only consistent way to break conformal invariance in a quantum theory of gravity is spontaneously in a finite locally conformal supersymmetric theory. This generically occurs whenever scalar fields are present. Covariant surface-integral expressions for the super-charge and four-momentum in terms of asymptotically constant spinor fields are derived. These are used to discuss stability and other aspects of the theory.


Bags Vs. Strings: Hadrons In Type I And Type Ii Superconducting Vacua, V. Parameswaran Nair, C. Rosenzweig Aug 1984

Bags Vs. Strings: Hadrons In Type I And Type Ii Superconducting Vacua, V. Parameswaran Nair, C. Rosenzweig

Publications and Research

Two popular models for hadronic structure are bags and strings. Both involve analogies with superconductivity. We claim that the most appropriate analogies are type I superconductors for bags and type II superconductors for strings. The structures of hadrons is somewhat different for the two situations. In principle, and in practice in the real world, it is the similarities which are most important. These include linear confining potentials, linearly rising Regge trajectories and short distance Coulomb potentials. These are all generic properties of bound states in a superconductor and the main distinctions between bags and strings is under what circumstances these …


Mixing Angles, B-Meson Life-Time In The Six-Quark Model Based On So(10) X U(1)Pq, V. Parameswaran Nair, Louis Michel, Kameshwar C. Wali Apr 1984

Mixing Angles, B-Meson Life-Time In The Six-Quark Model Based On So(10) X U(1)Pq, V. Parameswaran Nair, Louis Michel, Kameshwar C. Wali

Publications and Research

We show that a recently proposed multigenerational, grand unified model with three parameters (top-quark mass and two phases of Higgs vacuum expectation values) yields results in good agreement with the most recent phenomenological limits placed on the weak mixing angles of the quarks. These limits take into account the experimental value for B-meson life-time.


Peccei-Quinn Symmetry As Flavor Symmetry And Grand Unification, Aharon Davidson, V. Parameswaran Nair, Kameshwar C. Wali Apr 1984

Peccei-Quinn Symmetry As Flavor Symmetry And Grand Unification, Aharon Davidson, V. Parameswaran Nair, Kameshwar C. Wali

Publications and Research

We consider the possibility of identifying the Peccei-Quinn (PQ) symmetry as also the flavor symmetry in multigenerational grand unification schemes. The essential ingredient, a global, axial U(1) symmetry in the PQ mechanism to avoid the strong CP-violation problem provides useful constraints on the fermion —Higgs-boson couplings in the theory, thereby leading to identical "canonical" forms for fermion mass matrices in both the charged sectors. These forms are the conjectured Fritzsch-type matrices exhibiting the "nearest-neighbor" interactions in generation space. From among the popular schemes for grand unification, SO(10) emerges as one which has several advantages over the others for constructing multigenerational …


Low-Mass Solitons From Fractional Charges In Quantum Chromodynamics, A. P. Balachandran, V. Parameswaran Nair, N. Panchapakesan, S. G. Rajeev Dec 1983

Low-Mass Solitons From Fractional Charges In Quantum Chromodynamics, A. P. Balachandran, V. Parameswaran Nair, N. Panchapakesan, S. G. Rajeev

Publications and Research

Slansky, Goldman, and Shaw have proposed a model to account for the observation of fractionally charged states. We show that in this model, there are expected to be several low-mass solitons (four being in the mass range ∼20-60 MeV) associated with the third homotopy group π3(SU(3)/SO(3))=Z4, besides a low-mass (∼30 MeV) Z2 monopole. Confirmation of these levels and hence of the model has important implications for Cabrera's results on the magnetic monopole. An efficient algorithm for the calculation of π3(G/H) for a general Lie group G and a subgroup H is developed. It is pointed …


Breakdown Of Flavor Conservation In A Monopole Background, V. Parameswaran Nair Nov 1983

Breakdown Of Flavor Conservation In A Monopole Background, V. Parameswaran Nair

Publications and Research

We give a simple derivation of the catalysis of baryon decay and other flavor-changing processes by monopoles. The role of the axial anomaly is clarified. A general current-algebraic argument which clarifies the nature of flavor violation is also given.


Catalysis Of Flavor Nonconservation By Monopoles, V. Parameswaran Nair Aug 1983

Catalysis Of Flavor Nonconservation By Monopoles, V. Parameswaran Nair

Publications and Research

A simple argument based on current algebra is given to show how monopoles can lead to baryon decay and other flavor-changing processes.


Order Of Phase Transitions In A Field Theory, V. Parameswaran Nair Jul 1983

Order Of Phase Transitions In A Field Theory, V. Parameswaran Nair

Publications and Research

The relation between the gauge or global nature of a symmetry being broken and the order of the associated phase transition is clarified. First-order phase transitions in gauge theories are related to the asymptotic freedom of the Φ3 interaction in six dimensions. Spontaneous violation of lepton number in the standard electroweak theory provides a nontrivial illustration of our results.


Second-Order Phase Transitions, Inflationary Universe, And Formation Of Galaxies, V. Parameswaran Nair Jun 1983

Second-Order Phase Transitions, Inflationary Universe, And Formation Of Galaxies, V. Parameswaran Nair

Publications and Research

At the critical point of a second-order phase transition, statistical fluctuations are correlated and enhanced in amplitude. We explore this phenomenon in the early universe as a possible mechanism for the formation of galaxies. In an inflationary universe, such dynamical effects on galactic scales are consistent with the constraints imposed by the horizon. Spontaneous breakdown of lepton number provides a model where these ideas are realized. The two-point correlation function for density fluctuations is calculated and agrees with the observed correlation for galaxies. An estimate of the density contrast is shown to be of the required magnitude.


Generalized Bohr-Sommerfeld Rules For Anomalies With Applications To Symmetry Breakdown And Decoupling, A. P. Balachandran, V. P. Nair, C. G. Trahern Mar 1983

Generalized Bohr-Sommerfeld Rules For Anomalies With Applications To Symmetry Breakdown And Decoupling, A. P. Balachandran, V. P. Nair, C. G. Trahern

Publications and Research

In the presence of anomalies, the requirement that a classical symmetry group G has a proper action on the fermion measure or in the effective Lagrangian description imposes Bohr-Sommerfeld conditions on the anomalies, and often implies that G is broken to a subgroup H as well. We show these results in this paper and apply them to QCD and SU(5). In particular, constraints on the QCD order parameter are derived, and an argument is presented which suggests that the breakdown of the chiral flavor symmetry and the emergence of some sort of generation structure in QCD may be natural.


Soliton States In The Quantum-Chromodynamic Effective Lagrangian, A. P. Balachandran, V. Parameswaran Nair, S. G. Rajeev, A. Stern Mar 1983

Soliton States In The Quantum-Chromodynamic Effective Lagrangian, A. P. Balachandran, V. Parameswaran Nair, S. G. Rajeev, A. Stern

Publications and Research

The work of Skyrme has shown that the SU(2)×SU(2) chiral model has nontrivial topological sectors which admit solitons for generic chiral Lagrangians. In this paper, we study such models in the presence of baryon fields. The baryon number and strangeness of the solitons, and the bound states of the nucleon to the soliton are investigated. It is found that long-lived levels with large baryon number B and strangeness (≳6 in magnitude) and masses somewhere in the range 1.8 to 5.6 GeV must exist. Some of these levels have half-integral electric charge and exotic relation between B and spin s (e.g., …


Exotic Levels From Topology In The Quantum-Chromodynamic Effective Lagrangian, A. P. Balachandran, V. Parameswaran Nair, S. G. Rajeev, A. Stern Oct 1982

Exotic Levels From Topology In The Quantum-Chromodynamic Effective Lagrangian, A. P. Balachandran, V. Parameswaran Nair, S. G. Rajeev, A. Stern

Publications and Research

Skyrme has shown that the SU ⊗ SU(2) chiral model has nontrivial topological sectors with static solutions for suitable Lagrangians. The baryon number B and strangeness of these sectors have been studied, and the existence of bound states of the nucleon field to the lightest solitons is shown. It is found that there must be long-lived levels with |B|≳6 and |s|≳6 and 1.8 GeV≲m≲5.6 GeV, some having half-integral charge and exotic relation between B and s, that can be pair produced in, say, e+e− collisions.