Absorber theory

Durrant, A.V. (1980). A derivation of optical field quantization from absorber theory, Proc. Roy. Soc. (London) A370,41-59. 

In terms of Wheeler-Feynman absorber theory [47] a standing wave, consisting of synchronized retarded and advanced components, originating at emitter and absorber respectively, constitutes the wave function of a photon and it extends over the entire region between emitter and absorber. 

The idea of a closed space-time manifold with an involution has been mooted on the basis of nuclear synthesis (figure 2.6), number theory (figure 2.8), historical argument (4.4), absorber theory (figure 4.8) and chirality (5.9.3). All of these schemes can now be combined into a single construct based on curved Thierrin space-time. 

This definition of an electromagnetic interaction corresponds exactly with the absorber theory of Wheeler and Feynman (1945). According to this theory an accelerated charge in otherwise charge-free space does not radiate... 

If the superposition of point-source solutions is determined by a Green function , then by analogy with Wheeler-Feynman absorber theory the total interaction results from a symmetrical combination of retarded and advanced Green functions. On dehning these Green functions to be compatible with space-time geometry (Riemann tensor) the interaction is shown to be consistent with Einstein s field equations. 

Cramer, J.G. (1980) Generalized absorber theory and the Einstein-Podolsky-Rosen paradox, Phys. Rev.D, 1980 (22) 362-376. 

Korenev, B. G., Reznikov, L. M. (1993). Dynamic vibration absorbers Theory and technical applications (1st ed.). England John Wiley Sons Ltd. 

In statistical mechanics (e.g. the theory of specific heats of gases) a degree of freedom means an independent mode of absorbing energy by movement of atoms. Thus a mon-... 

For two Bom-Oppenlieimer surfaces (the ground state and a single electronic excited state), the total photodissociation cross section for the system to absorb a photon of energy ai, given that it is initially at a state x) with energy can be shown, by simple application of second-order perturbation theory, to be [89]... 

Another group of approaches for handling the R-T effect are those that employ various forms of effective Hamiltonians. By applying pertuibation theory, it is possible to absorb all relevant interactions into an effective Hamiltonian, which for a particular (e.g., vibronic) molecular level depends on several parameters whose values are determined by fitting available experimental data. These Hamiltonians are widely used to extract from high-resolution [e.g.. 

Theoretical Models of the Response Surface Mathematical models for response surfaces are divided into two categories those based on theory and those that are empirical. Theoretical models are derived from known chemical and physical relationships between the response and the factors. In spectrophotometry, for example, Beer s law is a theoretical model relating a substance s absorbance. A, to its concentration, Ca... 

From bolometer theory (1) the change in film temperature is proportional to the absorbed power and thermal resistance (inverse of the thermal conductance) and is given by the following ... 

As a pipeline is heated, strains of such a magnitude are iaduced iato it as to accommodate the thermal expansion of the pipe caused by temperature. In the elastic range, these strains are proportional to the stresses. Above the yield stress, the internal strains stiU absorb the thermal expansions, but the stress, g computed from strain 2 by elastic theory, is a fictitious stress. The actual stress is and it depends on the shape of the stress-strain curve. Failure, however, does not occur until is reached which corresponds to a fictitious stress of many times the yield stress. 

The stagnant-film model discussed previously assumes a steady state in which the local flux across each element of area is constant i.e., there is no accumulation of the diffusing species within the film. Higbie [Trans. Am. Jn.st. Chem. Eng., 31,365 (1935)] pointed out that industrial contactors often operate with repeated brief contacts between phases in which the contact times are too short for the steady state to be achieved. For example, Higbie advanced the theory that in a packed tower the liquid flows across each packing piece in laminar flow and is remixed at the points of discontinuity between the packing elements. Thus, a fresh liquid surface is formed at the top of each piece, and as it moves downward, it absorbs gas at a decreasing rate until it is mixed at the next discontinuity. This is the basis of penetration theoiy. 

Centrifugal pumps are made up of several components and are expected to cope in a multitude of environments, some quite hostile, fin understanding of houi they luorh, uihy they tuorh, luhy and houi they go turong and luhat to da about It can only come from a mix of theory and experience, hut the theory needs to be presented in a form which Is absorbable and Interesting if it is to he retained... 

This model was later expanded upon by Lifshitz [33], who cast the problem of dispersive forces in terms of the generation of an electromagnetic wave by an instantaneous dipole in one material being absorbed by a neighboring material. In effect, Lifshitz gave the theory of van der Waals interactions an atomic basis. A detailed description of the Lifshitz model is given by Krupp [34]. 

---