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Theorems, use

This is the BINOMIAL THEOREM. Using a Taylor Expansion, we can find the total probability for items taken r at a time as ... [Pg.209]

Derive both of the Ehrenfest theorems using equation (3.72). [Pg.105]

The derivation of the electrostatic properties from the multipole coefficients given below follows the method of Su and Coppens (1992). It employs the Fourier convolution theorem used by Epstein and Swanton (1982) to evaluate the electric field gradient at the atomic nuclei. A direct-space method based on the Laplace expansion of 1/ RP — r has been described by Bentley (1981). [Pg.176]

D. M. Carbeny, J. C. Reid, G. M. Wang, E. M. Sevick, D. J. Searles, and D. J. Evans, Fluctuations and irreversibility an experimental demonstration of a second-law-hke theorem using a colloidal particle held in an optical trap. Phys. Rev. Lett. 92, 140601 (2004). [Pg.117]

The Stone-Weierstrass theorem uses another notion of approximation uniform approximation. [Pg.99]

In the case of (5, 3)-polycycles, for every given number we have an example of a (5, 3)-boundary sequence, which admits exactly that number of fillings. The statement and the proof of this theorem used the elementary polycycles presented in Chapter 7 (especially, E, Ci, and C3 from Figure 7.2). [Pg.58]

One of the great strengths of MO theory is the guidance it provides for the assignment of photoelectron spectra by means of Koopmans theorem. Using physical assumptions which closely parallel those of Koopmans theorem, we have used the spin-coupled orbitals to examine simple valence bond estimates of the ionization potentials. We find that the results for the lowest ionization potentials are at least as good as those derived from Koopmans theorem, while the higher potentials appear to be considerably more reliable. [Pg.52]

The Derjaguin idea, a mainstay in colloid science since its 1934 publication, was rediscovered by nuclear physicists in the 1970s. In the physics literature one speaks of "proximity forces," surface forces that fit the criteria already given. The "Derjaguin transformation" or "Derjaguin approximation" of colloid science, to convert parallel-surface interaction into that between oppositely curved surfaces, becomes the physicists "proximity force theorem" used in nuclear physics and in the transformation of Casimir forces.23... [Pg.14]

The equivalence of (8.9) and (8.10) is shown in appendix 8.1. Application of the Wigner-Eckart theorem using (8.10) yields the result... [Pg.380]

Although the application of KirchhofFs laws offers basic tools to analyze a network, knowledge of certain network theorems, use of network equivalence, and use of reduction procedures simplify the process of network analysis. Basically, these theorems are applicable for linear networks. [Pg.73]

Proof. The proof of this is just like the argument in the theorem, using (M aB)q M a(Bq) and applying the lemma to B-modules rather than T-modules. ... [Pg.113]

The Melnikov integral is more suitable for theoretical purposes to prove theorems using model Hamiltonians. On the other hand. Lie perturbation theory is applicable to realistic systems such as clusters. For an application of Lie perturbation theory to clusters, see Ref. 23. [Pg.340]

The spectral density theorem, using Eq. (5.6), can also be written in terms of the correlation function o( )... [Pg.101]

Proof Solutions of (2.7) are bounded in L. Indeed, Q <0 for all large Q independent of x and x < 0 when Q is near P - that is, when x is large. The result is now a standard application of the Poincare-Bendixson theorem using the Dulac criterion (discussed in Chapter 1) to eliminate nontrivial periodic orbits and cycles of steady states in L. Indeed, since... [Pg.188]

Although stability may in principle be computed, the calculation is extremely complicated. Numerical calculations suggest the asymptotic stability of the limit cycle, but the stability has not been rigorously established. Assuming that the solution is asymptotically stable, a secondary bifurcation can be shown to occur. The argument is quite technical and requires a form of a Poincare map in the appropriate function space it is analogous to the bifurcation theorem used in Chapter 3 for bifurcation from a simple eigenvalue. The principal theorem takes the form of a bifurcation statement. [Pg.240]

The problem in which we are more interested is the quantum mechanics of periodic lattices which have been perturbed by the presence of defects. There is considert able experimental evidence for the association of discrete localized states with lattice defects of one sort or another the introduction of a perturbation into the quantum-mechanical problem should lead naturally to the prediction of these states. Quite recently Slater (18) has generalized a theorem used by Wannier for the discussion of excited states of crystals and through its use has clarified the whole problem of electronic motions in perturbed periodic lattices. It is possible to give an essentially non-mathematical discussion of Slater s treatment, as it is one which lends itself to simple graphical illustration. [Pg.58]

This paper is organized as follows. In Section II.B, we give a short account of the most popular definitions of PAB and we propose a generalized definition. In Section II.C, we briefly review the parametric frequency converter model and Glauber s theorem useful for our analysis of PAB. In Section II.D, we show discrepancies between three definitions of PAB for quantum nonstationary fields. In Section III.E, we show that there are classical non-stationary fields exhibiting apparently PAB according to the standard definitions. [Pg.517]

In Sec. A-l, an abbreviated treatment of matrix and vector norms is presented, and in Sec. A-2, mathematical theorems used in the text are presented. [Pg.583]

As mentioned above, the nuclei are assumed to be fixed and are thus nothing more than sources of an external electrostatic potential in which the electrons move. If there is no magnetic field external to the molecule under consideration, and if external electric fields are time-independent, we arrive at the so-called electrostatic limit of relativistic density functional theory. Note that most molecular systems fall within this regime. In this case, one can prove the relativistic Hohen-berg-Kohn theorem using the charge density, p(r) = J f), only. This leads to a definition of an exchange-correlation functional -Exc[p( )]... [Pg.606]

As you see, the main difference is the need to calculate an extra potential term to represent the attraction between the electron and a second nucleus. We can calculate the expectation values for any approximate trial function exactly as in the case of the hydrogen atom, then optimize the result using the variation theorem using any available disposable parameter available. [Pg.195]

Calculation of the number of pairs, triplets or larger ensembles of one kind of atom randomly dispersed on a plane surface containing two kinds is a simple application of binomial theorem. Use of the results in real systems is however predicated on a number of assumptions, and conditions that have to be met. These may be enumerated as follows. [Pg.236]

The Hellmann-Feynman theorem used in developing the formula as a derivative of the total energy has its origin in the work of H. G. A. Hell-mann (1937) Einfuhrung in die Quantenchemie, Leipzig, page 285, and in the work of R. P. Feynman from 1939 published in Phys. Rev. 56, 340. [Pg.196]

Equation (14.24) is an example of the Hellmann-Feynman theorem.] Using these last two equations in the molecular electronic virial theorem (14.23), we get... [Pg.463]

In several plaees in this book, we need to use similar proofs with Lagrange multipliers. This is why we will demonstrate how to prove the same theorem using this technique (see Appendix N available at booksite.elsevier.com/978-0-444-59436-5 on p. el21). [Pg.234]

We will prove this theorem using the variational principle in a way shown first by Levy. The variational principle states that... [Pg.677]


See other pages where Theorems, use is mentioned: [Pg.486]    [Pg.103]    [Pg.115]    [Pg.126]    [Pg.269]    [Pg.198]    [Pg.59]    [Pg.154]    [Pg.483]    [Pg.235]    [Pg.59]    [Pg.465]    [Pg.400]    [Pg.442]    [Pg.230]    [Pg.11]    [Pg.395]    [Pg.486]    [Pg.301]    [Pg.574]    [Pg.98]   
See also in sourсe #XX -- [ Pg.625 , Pg.626 ]




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