Search results for "Formalism"

showing 10 items of 357 documents

Analytical formulation of the axial behavior of apodized general Bessel beams

1999

We present an analytical formula for the evaluation of the axial-irradiance distribution of general Bessel beams apodized by a radially-nonsymmetric window. Our approach is based on the similarity between the axial behavior of such beams and the propagation properties of a properly modified version of the window transmittance. To illustrate our formalism, we analyze the axial behavior of some complex beams.

Physicsbusiness.industryTranscendental equationWave propagationAtomic and Molecular Physics and OpticsElectronic Optical and Magnetic Materialssymbols.namesakeFormalism (philosophy of mathematics)OpticsApodizationsymbolsTransmittancePhysics::Accelerator PhysicsElectrical and Electronic EngineeringPhysical and Theoretical ChemistrybusinessBessel functionOptics Communications
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Su(4) approach to fourfold degenerate electronic states of some hexafluoride molecules

2003

Abstract We show that two appropriate realizations of the su (4) algebra allow the construction of all electronic operators needed for the study of vibronic and rovibronic interactions in a G ′ electronic state. In each case a full bosonic realization is made and all matrix elements are calculated. Illustrations of our formalism and comparisons with previous approaches are made in the case of ν 5 ( F 2 g ) and ν 3 ( F 1 u ) modes.

Physicschemistry.chemical_compoundFormalism (philosophy of mathematics)HexafluoridechemistryJahn–Teller effectQuantum mechanicsDegenerate energy levelsMoleculePhysical and Theoretical ChemistrySpectroscopyAtomic and Molecular Physics and OpticsElectronic statesJournal of Molecular Spectroscopy
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Technical note: Monte-Carlo dosimetry of the HDR 12i and Plus 192Ir sources.

2001

In this study a complete set of dosimetric data for the GammaMed high dose rate (HDR) 12i and Plus 192 Ir sources are presented. These data have been calculated by means of the Monte Carlo simulation code GEANT3. Absolute dose rate distributions in water are presented as conventional two dimensional (2D) Cartesian look-up tables, and in the TG43 formalism.

Physicsmedicine.medical_treatmentBrachytherapyMonte Carlo methodBrachytherapyBiophysicsWaterTechnical noteGeneral MedicineIridium RadioisotopesBiophysical PhenomenaComputational physicslaw.inventionFormalism (philosophy of mathematics)lawmedicineEconometricsDosimetryAnisotropyCartesian coordinate systemDose rateRadiometryMonte Carlo MethodMedical physics
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The ground state rotational spectrum of SO2F2

2003

Abstract The analysis of the ground state rotational spectrum of SO 2 F 2 [K. Sarka, J. Demaison, L. Margules, I. Merke, N. Heineking, H. Burger, H. Ruland, J. Mol. Spectrosc. 200 (2000) 55] has been performed with the Watson’s Hamiltonian up to sextic terms but shows some limits due to the A and S reductions. Since SO 2 F 2 is a quasi-spherical top, it can also be regarded as derived from an hypothetical XY 4 molecule. Thus we have developed a new tensorial formalism in the O (3)⊃ T d ⊃ C 2 v group chain (M. Rotger, V. Boudon, M. Loete, J. Mol. Spectrosc. 216 (2002) 297]. We test it on the ground state of this molecule using the same experimental data (10 GHz–1 THz region, J up to 99). Bot…

Physicssymbols.namesakeFormalism (philosophy of mathematics)Quantum mechanicsRotational spectrumsymbolsRotational spectroscopyPhysical and Theoretical ChemistryGround stateHamiltonian (quantum mechanics)SpectroscopyAtomic and Molecular Physics and OpticsJournal of Molecular Spectroscopy
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Isospin Mixing Within the Symmetry Restored Density Functional Theory and Beyond

2013

We present results of systematic calculations of the isospin-symmetry-breaking corrections to the superallowed I=$0+,T=1 --> I=0+,T=1 beta-decays, based on the self-consistent isospin- and angular-momentum-projected nuclear density functional theory (DFT). We discuss theoretical uncertainties of the formalism related to the basis truncation, parametrization of the underlying energy density functional, and ambiguities related to determination of Slater determinants in odd-odd nuclei. A generalization of the double-projected DFT model towards a no core shell-model-like configuration-mixing approach is formulated and implemented. We also discuss new opportunities in charge-symmetry- and cha…

Physicsta114Nuclear TheoryEnergy density functionalNuclear TheoryFOS: Physical sciencesGeneral Physics and AstronomyNuclear Theory (nucl-th)Formalism (philosophy of mathematics)Theoretical physicsIsospinSlater determinantDensity functional theoryNuclear ExperimentFunctional theoryNuclear theoryNuclear densityActa Physica Polonica B
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El II Congreso de Arquitectos Soviéticos (1954). Los inicios de la transición poststaliniana

1987

EL II CONGRESO DE ARQUITECTOS SOVIETICOS PUEDE SER CONSIDERADO COMO UNO DE LOS PRIMEROS INTENTOS, SI NO EL PRIMERO, DE INICIAR LA DESESTALINIZACION EN EL CAMPO DEL ARTE POR PARTE DEL HOMBRE FUERTE DEL P.C.US., NIKITA KRUSCHOV, PROCESO QUE TENDRIA, CON CARACTER GENERAL, SU PUNTO ALGIDO EN EL XX CONGRESO DEL PARTIDO EN 1956. EL II CONGRESO DE ARQUITECTOS BUSCA, POR UNA PARTE, ROMPER CON EL CLASICISMO MONUMENTALISTA, TAN CARO A STALIN EN LOS DOMINIOS DE LA ARQUITECTURA, PERO SIN CAER EN SOLUCIONES FUNCIONALISTAS QUE RETROTRAIGAN LA ARQUITECTURA SOVIETICA A LOS AUN DENOSTADOS TIEMPOS DE LA VANGUARDIA POSTREVOLUCIONARIA. SO PRETEXTO DE ADECUAR LA ARQUITECTURA A NUEVAS TECNOLOGIAS EN EL CAMPO DE …

Política urbanísticaCongresosUNESCO::HISTORIA::Historia por épocas::Historia antiguaFormalismoArquitectura contemporánea:HISTORIA::Historia por épocas::Historia antigua [UNESCO]Análisis crítico
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Thermodynamics of Electrochemical Systems

2004

A discussion of the fundamentals of thermodynamic theory describing electrochemical systems is presented. The basic relationships are deduced as properties of the electrochemical potential. The theory introduces an observable electric potential that is defined at every position within the electrochemical system as the potential of a reversible electrode placed there. To provide a good test of the formalism, five systems have been studied including equilibrium and nonequilibrium. The formalism emphasizes the advantages of the electric current density in order to characterize one of the degrees of irreversibility and the electrical equilibrium. Finally, the electrostatic potential is discusse…

Position (vector)Formalism (philosophy)ChemistryElectrodeMaterials ChemistryNon-equilibrium thermodynamicsThermodynamicsObservableElectric potentialPhysical and Theoretical ChemistryElectric currentSurfaces Coatings and FilmsElectrochemical potentialThe Journal of Physical Chemistry B
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Reference-point-independent dynamics of molecular liquids and glasses in the tensorial formalism.

2002

We apply the tensorial formalism to the dynamics of molecular liquids and glasses. This formalism separates the degrees of freedom into translational and orientational ones. Using the Mori-Zwanzig projection formalism, the equations of motion for the tensorial density correlators S(lmn,l'm'n')(q-->,t) are derived. For this we show how to choose the slow variables such that the resulting Mori-Zwanzig equations are covariant under a change of the reference point of the body fixed frame. We also prove that the memory kernels obtained from mode-coupling theory (MCT) including all approximations preserve the covariance. This covariance makes, e.g., the glass transition point, the two universal s…

Potential energy landscapePhysicsGlass transition pointFormalism (philosophy of mathematics)Classical mechanicsEquations of motionCovariant transformationLinear molecular geometryMoment of inertiaCovariancePhysical review. E, Statistical, nonlinear, and soft matter physics
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From pseudo-bosons to pseudo-Hermiticity via multiple generalized Bogoliubov transformations

2016

We consider the special type of pseudo-bosonic systems that can be mapped to standard bosons by means of generalized Bogoliubov transformation and demonstrate that a pseudo-Hermitian systems can be obtained from them by means of a second subsequent Bogoliubov transformation. We employ these operators in a simple model and study three different types of scenarios for the constraints on the model parameters giving rise to a Hermitian system, a pseudo-Hermitian system in which the second the Bogoliubov transformations is equivalent to the associated Dyson map and one in which we obtain D-quasi bases.

Pseudo-bosonSwanson modelFOS: Physical sciencesModel parametersPT-symmetry01 natural sciences0103 physical sciences010306 general physicsSettore MAT/07 - Fisica MatematicaMathematical PhysicsQCBosonMathematical physicsPhysicsCondensed Matter::Quantum GasesQuantum Physics010308 nuclear & particles physicsStatistical and Nonlinear PhysicsMathematical Physics (math-ph)Condensed Matter PhysicsHermitian matrixFormalism (philosophy of mathematics)Bogoliubov transformationpseudo-HermiticityQuantum Physics (quant-ph)Statistical and Nonlinear Physic
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Quantum Entanglement and the Issue of Selective Influences in Psychology: An Overview

2012

Similar formalisms have been independently developed in psychology, to deal with the issue of selective influences (deciding which of several experimental manipulations selectively influences each of several, generally non-independent, response variables), and in quantum mechanics (QM), to deal with the EPR entanglement phenomena (deciding whether an EPR experiment allows for a "classical" account). The parallels between these problems are established by observing that any two noncommuting measurements in QM are mutually exclusive and can therefore be treated as analogs of different values of one and the same input. Both problems reduce to that of the existence of a jointly distributed syst…

Pure mathematics05 social sciencesQuantum entanglement01 natural sciencesRotation formalisms in three dimensions050105 experimental psychologysymbols.namesakeJoint probability distribution0103 physical sciencessymbols0501 psychology and cognitive sciencesStatistical physicsEPR paradox010306 general physicsParallelsRandom variableValue (mathematics)MathematicsVariable (mathematics)
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