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Lorentz different

As in the spin 0 and spin case we could next introduce creation and anniliilation operators. This is most conveniently done by working with the representatives that satisfy in a given Lorentz frame the three dimensional transversality condition, i.e., by working in the radiation gauge. We shall, however, adopt a slightly different procedure, which is outlined in the next section. [Pg.560]

The Coulomb gauge theory and the Lorentz gauge theory thus both describe the same physical phenomena, but they handle one aspect of the physical situation, namely, the Coulomb interaction, in fundamentally different ways. In the Coulomb gauge the interaction is... [Pg.657]

In the present section we shall make this difficulfy apparent in a somewhat different way by showing that it is not possible to satisfy the asymptotic condition when the theory is formulated in terms of an unsubtracted hamiltonian of the form jltAll(x) — JS0JV. We shall work in the Lorentz gauge, where the relativistic invariance of the theory is more obvious. [Pg.699]

Lorentz, A., Schwengberg, S., Sellge, G., Manns, M.P. and Bischoff, S.C. (2000) Human intestinal mast cells are capable of producing different cytokine profiles role of IgE receptor cross-linking and YEA. Journal of Immunology 164, 43-48. [Pg.401]

It should be clear that the Darwin equation with its special LoRENTZ-polariza-tion factor as reported by Warren ([97], Eq. (4.7)) is only valid for unpolarized laboratory sources and the rotation-crystal method. An application to different setup geometries, for example to synchrotron GIWAXS data of polymer thin films is not appropriate. [Pg.109]

Warning. For isotropic materials the ID projection /, and the Lorentz correction yield different ID intensities. Both are related by... [Pg.157]

Four-vectors for which the square of the magnitude is greater than or equal to zero are called space-like when the squares of the magnitudes are negative they are known as time-like vectors. Since these characteristics arise from the dot products of the vectors with reference to themselves, which are world scalars, the designations are invariant under Lorentz transformation[17], A space-like 4-vector can always be transformed so that its fourth component vanishes. On the other hand, a time-like four-vector must always have a fourth component, but it can be transformed so that the first three vanish. The difference between two world points can be either space-like or time-like. Let be the difference vector... [Pg.147]

The condition for a time-like difference vector is equivalent to stating that it is possible to bridge the distance between the two events by a light signal, while if the points are separated by a space-like difference vector, they cannot be connected by any wave travelling with the speed c. If the spatial difference vector r i — r2 is along the z axis, such that In — r2 = z — z2, under a Lorentz transformation with velocity v parallel to the z axis, the fourth component of transforms as... [Pg.147]

The above reasoning has led to the fireball internal-external shocks model. This model is rather independent of the nature of the central engine. The latter one is just required to produce highly relativistic outflow, either in the form of kinetic energy or as Poynting flux. The radiation is produced in (collisionless) shocks. These can either occur due to interaction of the outflow with the cir-cumstellar material ( external shocks ) or due to interactions of different portions of the outflow with different Lorentz-factors, so-called internal shocks . [Pg.312]

Figure 9. Two trajectories of the periodic hard-disk Lorentz gas. They start from the same position but have velocities that differ by one part in a million, (a) Both trajectories depicted on large spatial scales, (b) Initial segments of both trajectories showing the sensitivity to initial conditions. Figure 9. Two trajectories of the periodic hard-disk Lorentz gas. They start from the same position but have velocities that differ by one part in a million, (a) Both trajectories depicted on large spatial scales, (b) Initial segments of both trajectories showing the sensitivity to initial conditions.
Figure 12. The diffusive modes of the periodic Yukawa-potential Lorentz gas represented by their cumulative function depicted in the complex plane ReFk,hnFk) for two different nonvanishing wavenumbers k. The horizontal straight line is the curve corresponding to the vanishing wavenumber k = 0 at which the mode reduces to the invariant microcanonical equilibrium state. Figure 12. The diffusive modes of the periodic Yukawa-potential Lorentz gas represented by their cumulative function depicted in the complex plane ReFk,hnFk) for two different nonvanishing wavenumbers k. The horizontal straight line is the curve corresponding to the vanishing wavenumber k = 0 at which the mode reduces to the invariant microcanonical equilibrium state.
It should be noted that the Raman-inactive soft mode is observed in the temperature region above Tc. A spectral shape completely different from that of the Lorentz-type peak function indicates the defect-induced Raman scattering (DIRS) in the paraelectric phase of ST018. When centrosymmetry is locally broken in the paraelectric phase, the nominally Raman-inactive soft mode is optically activated locally to induce DIRS in the soft mode. [Pg.106]

The return to equilibrium of a polarized region is quite different in the Debye and Lorentz models. Suppose that a material composed of Lorentz oscillators is electrically polarized and the static electric field is suddenly removed. The charges equilibrate by executing damped harmonic motion about their equilibrium positions. This can be seen by setting the right side of (9.3) equal to zero and solving the homogeneous differential equation with the initial conditions x = x0 and x = 0 at t = 0 the result is the damped harmonic oscillator equation ... [Pg.260]

Moreover, Anastasovski et al. [79] have interpreted the basic EM field equations in a new and different way. Thereby the Lorentz condition L = 0 has been discarded, and Eqs. (A.l) and (A.2) have been modified to the form... [Pg.63]

Similarly, can be used to suggest a way out of the de Broglie paradox [42], which points out that momentum and energy transform differently under Lorentz transformation from frequency. This paradox led de Broglie to postulate the existence of empty waves, which, however, have never been observed empirically. It can therefore be suggested that the Lorentz frequency transform must always be applied to... [Pg.101]

From Eq, (1) it is clear that a model of crystal polarization that is adequate for the description of the piezoelectric and pyroelectric properties of the P-phase of PVDF must include an accurate description of both the dipole moment of the repeat unit and the unit cell volume as functions of temperature and applied mechanical stress or strain. The dipole moment of the repeat unit includes contributions from the intrinsic polarity of chemical bonds (primarily carbon-fluorine) owing to differences in electron affinity, induced dipole moments owing to atomic and electronic polarizability, and attenuation owing to the thermal oscillations of the dipole. Previous modeling efforts have emphasized the importance of one more of these effects electronic polarizability based on continuum dielectric theory" or Lorentz field sums of dipole lattices" static, atomic level modeling of the intrinsic bond polarity" atomic level modeling of bond polarity and electronic and atomic polarizability in the absence of thermal motion. " The unit cell volume is responsive to the effects of temperature and stress and therefore requires a model based on an expression of the free energy of the crystal. [Pg.196]

After their creation, positive ions are accelerated through a voltage difference V. They thus acquire a velocity t> that depends on their mass m. Following acceleration, the ions enter a transversal magnetic field of intensity B. The orientation of this field does not modify the ions velocity but forces them on a circular trajectory that is a function of their m/z ratio. The fundamental relationship of dynamics F = ma (a designates acceleration), applied to ions of mass m on which a Lorentz force F = qv A B is exerted leads to the following relationship ... [Pg.292]


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See also in sourсe #XX -- [ Pg.155 ]




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