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Lamb equation

It should be noted that the Lamb equation is appropriate for a low frequency filter rather than a resonant phenomenon such as spectral absorption by the chromophores. Its asymptotic character at short wavelengths leads to a half-amplitude value that is quite different from the similar half-amplitude value for a resonant phenomenon of arbitrary resonance factor, Q. [Pg.81]

Another method is a series of exhaust dilution equations based on Wilson and Lamb " and a series of earlier papers summarized in ASHRAE. This method is based on wind tunnel tests on simplified buildings and is intended to provide conservative (low dilution) results. Wilson and Lamb compared the model to actual field data collected at a university campus and found that the model did indeed predict dilutions similar to measured worst-case dilutions suitable for a screening model. However, many cases resulted in conservative Linderpredictions of dilutions. ... [Pg.579]

According to the Dirac equation the 2Sm and 2P1/2 states coincide. It was, however, observed by Lamb and Rutherford that the 2level shift, one must take into account the quantum aspect of the electromagnetic field as well as those of the negaton-positon field. [Pg.641]

The new delightful book by Greenstein and Zajonc(9) contains several examples where the outcome of experiments was not what physicists expected. Careful analysis of the Schrddinger equation revealed what the intuitive argument had overlooked and showed that QM is correct. In Chapter 2, Photons , they tell the story that Einstein got the Nobel Prize in 1922 for the explaining the photoelectric effect with the concept of particle-like photons. In 1969 Crisp and Jaynes(IO) and Lamb and Scullyfl I) showed that the quantum nature of the photoelectric effect can be explained with a classical radiation field and a quantum description for the atom. Photons do exist, but they only show up when the EM field is in a state that is an eigenstate of the number operator, and they do not reveal themselves in the photoelectric effect. [Pg.26]

The complex wave frequency Q (= ico — F) is related to k via a dispersion relation. For an inviscid liquid, Lamb s equation is well-known as a classical approximation for the dispersion relation [10]... [Pg.240]

The approach described above is by no means complete or exclusive. For example, Lamb et al. (1975) have proposed an alternative route to assess the adequacy of the atmospheric diffusion equation. Their approach is based on the Lagrangian description of the statistical properties of nonreacting particles released in a turbulent atmosphere. By employing the boundary layer model of Deardorff (1970), the transition probability density p x, y, z, t x, y, z, t ) is determined from the statistics of particles released into the computed flow field. Once p has been obtained, Eq. (3.1) can then be used to derive an estimate of the mean concentration field. Finally, the validity of the atmospheric diffusion equation is assessed by determining the profile of vertical dififiisivity that produced the best fit of the predicted mean concentration field. [Pg.252]

Soon after the Schrodinger equation was introduced in 1926, several works appeared dealing with the fundamental problem of the nuclear motion in molecules. Very soon after, the relativistic equations were introduced for one-and two-electron systems. The experiments on the Lamb shift stimulated... [Pg.378]

L(0) = Z In 7, where I is the mean excitation potential appearing in Bethe s stopping power equation [Eq. (4)]. 7,(2) is proportional to the logarithm of average excitation energy, which is also involved in the Lamb shift [26]. 7,(—1) has been shown to be an optical... [Pg.16]

Figure 8.12 shows the projected conversion of S02 to sulfate as a function of the volume of water per cubic meter of air available for conversion in the aqueous phase, covering a range typical of haze particles, fogs, and clouds for atmospheric lifetimes which are typical for each (Lamb et al., 1987). As expected from Eq. (M), the conversion increases with the water available in the atmosphere. As we shall see, the aqueous-phase oxidation does indeed predominate in the atmosphere under many circumstances. Equations (G) and (M) apply as long as the partial pressure of SOz in the gas phase, so,, is measured simultaneously with the solution concentration of S(IV). [Pg.308]

The main contribution to the Lamb shift was first estimated in the nonrela-tivistic approximation by Bethe [8], and calculated by Kroll and Lamb [9], and by French and Weisskopf [10]. We have already discussed above qualitatively the nature of this contribution. In the effective Dirac equation framework the... [Pg.22]

The mass dependence of the correction of order a Za) beyond the reduced mass factor is properly described by the expression in (3.7) as was proved in [11, 12]. In the same way as for the case of the leading relativistic correction in (3.4), the result in (3.7) is exact in the small mass ratio m/M, since in the framework of the effective Dirac equation all corrections of order Za) are generated by the kernels with one-photon exchange. In some earlier papers the reduced mass factors in (3.7) were expanded up to first order in the small mass ratio m/M. Nowadays it is important to preserve an exact mass dependence in (3.7) because current experiments may be able to detect quadratic mass corrections (about 2 kHz for the IS level in hydrogen) to the leading nonrecoil Lamb shift contribution. [Pg.24]

Purely relativistic corrections are by far the simplest corrections to h3rper-fine splitting. As in the case of the Lamb shift, they essentially correspond to the nonrelativistic expansion of the relativistic square root expression for the energy of the light particle in (1.3), and have the form of a series over Zo j /m . Calculation of these corrections should be carried out in the framework of the spinor Dirac equation, since clearly there would not be any hyperfine splitting for a scalar particle. [Pg.165]

This experimental development was matched by rapid theoretical progress, and the comparison and interplay between theory and experiment has been important in the field of metrology, leading to higher precision in the determination of the fundamental constants. We feel that now is a good time to review modern bound state theory. The theory of hydrogenic bound states is widely described in the literature. The basics of nonrelativistic theory are contained in any textbook on quantum mechanics, and the relativistic Dirac equation and the Lamb shift are discussed in any textbook on quantum electrodynamics and quantum field theory. An excellent source for the early results is the classic book by Bethe and Salpeter [6]. A number of excellent reviews contain more recent theoretical results, and a representative, but far from exhaustive, list of these reviews includes [7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17]. [Pg.268]

The calculation of the Lamb shift due to B<3> is completed by using the equations... [Pg.151]

The last formulae can be obtained from the motion equation written in the Lamb form... [Pg.465]

In this section we discuss the nonrelativistic 0(3) b quantum electrodynamics. This discussion covers the basic physics of f/(l) electrodynamics and leads into a discussion of nonrelativistic 0(3)h quantum electrodynamics. This discussion will introduce the quantum picture of the interaction between a fermion and the electromagnetic field with the magnetic field. Here it is demonstrated that the existence of the field implies photon-photon interactions. In nonrelativistic quantum electrodynamics this leads to nonlinear wave equations. Some presentation is given on relativistic quantum electrodynamics and the occurrence of Feynman diagrams that emerge from the B are demonstrated to lead to new subtle corrections. Numerical results with the interaction of a fermion, identical in form to a 2-state atom, with photons in a cavity are discussed. This concludes with a demonstration of the Lamb shift and renormalizability. [Pg.423]

The most essential properly of acoustic vibrations in a nanoparticle is the existence of minimum size-quantized frequencies corresponding to acoustic resonances of the particle. In dielectric nanociystals, the Debye model is not valid for evaluation of the PDOS if the radius of the nanociystal is less than 10 nm. The vibrational modes of a finite sphere were analyzed previously by Lamb (1882) and Tamura (1995). A stress-free boundary condition at the surface and a finiteness condition on both elastic displacements and stresses at the center are assumed. These boundary conditions yield the spheroidal modes and torsional modes, determined by the following eigenvalue equations ... [Pg.109]

At this time, Stockman, et. al134. and Lamb135 and Baylor et. al.136 are using empirical expressions for the absorption spectrums of human chromophores. Stockman, et. al. are using a conventional arithmetic series in even powers of the variable. They make no claim to a physical foundation for their series. Lamb says It needs to be emphasized that the above (his) represents no more than an exercise in curve-fitting, and that neither equation (1) nor equation (2) has any known physical significance.. . These equations (his equation 2 in particular) are basically attempts to approximate the Helmholtz-Boltzmann equation as it is derived from the Fermi-Dirac equation, by empirical... [Pg.83]


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See also in sourсe #XX -- [ Pg.536 ]




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