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Connection formula general equations

We will describe, in some detail, one such modification, an effective Dirac equation (EDE) which was derived in a number of papers [7, 8, 9, 10]. This new equation is more convenient in many applications than the original BS equation, and we will derive some general formulae connected with this equation. The physical idea behind this approach is that in the case of a loosely bound system of two particles of different masses, the heavy particle spends almost all its life not far from its own mass shell. In such case some kind of Dirac equation for the light particle in an external Coulomb field should be an excellent starting point for the perturbation theory expansion. Then it is convenient to choose the free two-particle propagator in the form of the product of the heavy particle mass shell projector A and the free electron propagator... [Pg.6]

Let us, for a moment, consider a single particle in one dimension with a Hamiltonian of the type// = p2/2m + V(x). This is a second-order differential operator, and this means that the general solution to the inhomogeneous Eq. (3.51)—considered as a second-order differential equation—will consist of a linear superposition of two special solutions, where the coefficients will depend on the boundary conditions introduced. As a specific example, one could think of the two solutions to the JWKB problem, their connection formulas, and the Stoke s phenomenon for the coefficients. [Pg.130]

The ordinary Airy function A,(z) corresponds to this solution with A = 0. Equation (85) represents the famous connection formula for the WKB solutions crossing the turning point. As can now be easily understood, once we know all the Stokes constants the connections among asymptotic solutions are known and the physical quantities, such as the scattering matrix, can be derived. However, the Airy function is exceptionally simple and the Stokes constants are generally not known except for some special cases (40). [Pg.496]

The principal feature of this relationship is that F values are derived solely from molecular formulae and chemical structures and require no prior knowledge of any physical, chemical or thermochemical properties other than the physical state of the explosive that is, explosive is a solid or a liquid [72]. Another parameter related to the molecular formulae of explosives is OB which has been used in some predictive schemes related to detonation velocity similar to the prediction of bri-sance, power and sensitivity of explosives [35, 73, 74]. Since OB is connected with both, energy available and potential end products, it is expected that detonation velocity is a function of OB. As a result of an exhaustive study, Martin etal. established a general relation that VOD increases as OB approaches to zero. The values of VOD calculated with the use of these equations for some explosives are given in the literature [75] and deviations between the calculated and experimental values are in the range of 0.46-4.0%. [Pg.32]

Partitioning technique refers to the division of data into isolated sections and it was put into successful practice in connection with matrix operations. Lowdin, in his pioneering studies, [21, 22] developed standard finite dimensional formulas into general operator transformations, including treatments appropriate for both the bound state and the continuous part of the spectrum, see also details in later appendices. Complementary generalizations to resonance-type problems were initiated in Ref. [23], and simple variational formulations were demonstrated in Refs. [24,25]. Note that analogous forms were derived for the Liouville equation [26, 27] and further developed in connection with a retarded-advanced subdynamics formulation [28]. [Pg.86]

There is a connection between the Lagrangian representation based on advected particles and the Eulerian representation using concentration fields. As in the case of pure advection the solution of the advection-diffusion equation can be given in terms of trajectories of fluid elements. Equation (2.6) can be generalized for the diffusive case using the Feynman-Kac formula (see e.g. Durrett (1996)) as... [Pg.31]

Here is a useful leisure time exercise for a very attentive reader. The purpose is to understand the connection between virial expansion (8.7) and the well known van der Waals equation of state (i.e., the relationship between volume, pressure, and temperature) for an ordinary imperfect gas. You may have studied van der Waals equation in general physics and/or general chemistry class, it reads p- -a/V )(V — b) = NksT. Say, the volume is V, and the number of molecules in the gas is N. Then n = N/V. You can work out the pressure by differentiation p = — (9F/9V), where free energy F is defined by formula (7.19), F = U — TS = t/ + / , the internal energy U is given by (8.7), and... [Pg.156]

One mates the connection by counting the independent components of the irreducible tensor. For the completely symmetric r = [71,0,0] states (see the discussion above equation (15) for an explanation of this notation) this is given by equation (18) of Reference [16]. In three dimensions the F = [71,1,0] tableau, ie either the two box antisymmetric or the mixed symmetry tableaux, is associate (see Reference [5] p. 396 and Reference [6] p. 164) to the F = [71,0,0] tableau, i.e. a completely symmetric tableaux. Thus a second rank antisymmetric or a mixed symmetry tensor has the same dimension as the associate completely symmetric tensor. The three box completely antisymmetric F = [1,1,1] tableau is the associate tableau to the tableau with no boxes and is therefore a scalar. There aie more general formulas for the number of independent components of an irreducible tensor in D dimensions, however they are not required to achieve the above identification, see D.E. Littlewood, The Theory of Group Characters (Oxford University Press, Oxford, 1950), equation (11.8 6), p. 236. [Pg.388]

The MO measurements provide information about the angular distribution of molecules in the x, y, and z film coordinates. To extract MO data from IR spectra, the general selection rule equation (1.27) is invoked, which states that the absorption of linearly polarized radiation depends upon the orientation of the TDM of the given mode relative to the local electric field vector. If the TDM vector is distributed anisotropically in the sample, the macroscopic result is selective absorption of linearly polarized radiation propagating in different directions, as described by an anisotropic permittivity tensor e. Thus, it is the anisotropic optical constants of the ultrathin film (or their ratios) that are measured and then correlated with the MO parameters. Unlike for thick samples, this problem is complicated by optical effects in the IR spectra of ultrathin films, so that optical theory (Sections 1.5-1.7) must be considered, in addition to the statistical formulas that establish the connection between the principal values of the permittivity tensor s and the MO parameters. In fact, a thorough study of the MO in ultrathin films requires judicious selection not only of the theoretical model for extracting MO data from the IR spectra (this section) but also of the optimum experimental technique and conditions [angle(s) of incidence] for these measurements (Section 3.11.5). [Pg.266]

A more formal connection between the fractional likelihoods and probabilities is reserved for Section 2.4. For now, it is sufficient to note that formulae analogous to Equations (2.8) and (2.9) extend beyond aromatic substitution. The generality is conveyed by labeling the likelihood fractions by subscripts 1 and 2 /j and/2. Then, if one considers the fractions as logarithm arguments and multiplies the results by -1, one arrives at ... [Pg.19]


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See also in sourсe #XX -- [ Pg.21 , Pg.22 , Pg.23 ]




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