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Spin field

The choice of ijr 2 — 1, together with the antiunitary character of U(it), guarantees the invariance of the equal time commutation rules under U(it). With these definitions of the transformation properties of the spin field operators one verifies that... [Pg.691]

Here x G RD and ip(x) is a spin field having N (flavor) components, ipa(x) (a = 1,2, summation over flavor and spin indices being... [Pg.211]

In this connection it should finally be mentioned that Comay [63] and Hunter [64] have discussed the field concept by Evans and Vigier on the basis of conventional electromagnetic theory where the 4-current of Eq. (22) vanishes in the vacuum. Their analysis leads to the obvious conclusion that the field vanishes in such a case. This does, however, not rule out the existence of B(3) when there is a nonzero 4-current of the type (26) introduced by de Broglie, Vigier and Evans. Thus, without a Proca-type equation (22), no steady-state magnetic spin field can exist in a rest frame K. ... [Pg.48]

With a nonzero rest mass one would at a first glance expect a photon gas to have three degrees of freedom two transverse and one longitudinal. This would alter Planck s radiation law by a factor of, in contradiction with experience [20]. A detailed analysis based on the Proca equation shows, however, that the B3 spin field cannot be involved in a process of light absorbtion [5]. This is also made plausible by the present model of Sections VII and VIII, where the spin field is carried away by the pilot field. As a result, Planck s law is recovered in all practical cases [20]. In this connection it has also to be observed that transverse photons cannot penetrate the walls of a cavity, whereas this is the case for longitudinal photons which would then not contribute to the thermal equilibrium [43]. [Pg.49]

The presence of OH or OD radicals in these systems is not surprising since they are present in irradiated pure ice itself at this temperature. Other resonances dose to the free spin field position differ from one solute to another, and are discussed in the next section. A more significant observation is the presence of H atoms in a number of widely different systems and yet their absence in pure ice itself. [Pg.189]

Much of our understanding of critical phenomena is based on the Landau-Ginzburg model of a ferromagnet. This model concentrates on the local magnetization, represented by an m-component vector field Sa (r), a = 1,..., m. often called a classical spin field . The interaction of the spin field is described by the Landau-Ginzburg Hamiltonian... [Pg.118]

Evaluating the model (A 7.1) one finds that it describes a second order pha.se transition occurring for h = 0 and a critical value r = re. The transition is signaled by long range correlations of the spin field or power-type... [Pg.118]

N. C. Petroni, P. Gueret, J. P. Vigier, and A. Kyprianidis, Second order wave equation for spin fields II. The Hilbert space of the states, Phys. Rev. D (Special Issue Particles and Fields) 33(6), 1674-1680(1986). [Pg.184]

D. Antisymmetric Stresses, Internal Spin Fields, and Vortex Viscosity in Magnetic Fluids... [Pg.66]

Accompanying the impeded particle rotation is the (kinematical) existence of an internal spin field 12 within the suspension, which is different from one-half the vorticity to = ( )V x v of the suspension. The disparity to — 2 between the latter two fields serves as a reference-frame invariant pseudovector in the constitutive relation T = ((to — 12), which defines the so-called vortex viscosity ( of the suspension. Expressions for (( ) as a function of the volume of suspended spheres are available (Brenner, 1984) over the entire particle concentration range and are derived from the prior calculations of Zuzovsky et ai (1983) for cubic, spatially-periodic suspension models. [Pg.66]

Surface composition analysis by neutral and ion impact radiation SCANIIR spins fields 8... [Pg.386]

We have not yet considered these effects in the non-relativistic Hamiltonian (2.1) on p. 67 (e.g., no spin-spin or spin-field interactions). The effects that we are now dealing with are so small-on the order of 10 kcal/mole-that they are of no importance for most applications, including UV-VIS, IR. Raman spectra, electronic structure, chemical reactions, intermolecular interactions, etc. This time, however, the situation is different we are going to study very subtle interactions using the NMR technique, which aims precisely at the energy levels that result from spin-spin and spin- magnetic field interactions. Even if these effects are very small, they can be observed. Therefore,... [Pg.762]

The energy function of the system for spin-spin and spin-field interactions is... [Pg.348]

Sample Spinning, Field/Frequency Lock, and Field Gradients... [Pg.3264]

Hz is simply the electron spin-field coupling given by Hj in (A4.17c),... [Pg.370]

The second-order interaction of the two terms in (11.8.15) thus leads to a spin-field term of tensor form, whose components will depend on the orientation of the molecule in the applied field. Although in (11.8.15) we only admitted the 1-electron terms of the full the 2-electron terms are handled in a similar way and are easily added (Problem 11.15). [Pg.400]


See other pages where Spin field is mentioned: [Pg.224]    [Pg.119]    [Pg.127]    [Pg.7]    [Pg.414]    [Pg.154]    [Pg.119]    [Pg.127]    [Pg.68]    [Pg.369]    [Pg.414]    [Pg.150]    [Pg.136]    [Pg.135]    [Pg.111]    [Pg.398]    [Pg.400]    [Pg.402]   
See also in sourсe #XX -- [ Pg.110 , Pg.111 ]




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