Propagation of light

Of this book Albert Einstein said Gives a really clear idea of the problem, especially the development of our knowledge concerning the propagation of light and the difficulties which arose from the apparently inevitable introduction of the ether. 

Maxwell s equations can be combined (61) to describe the propagation of light ia free space, yielding the following scalar wave equation ... 

Figure 18. Propagation of light in a typical fibre sensor.

The propagation of light in multiple scattering media is quantified usually on the level of radiative transfer or particle diffusion. Scattering, absorption, and emission are considered as independent statistical processes, and the consequences of wave character are either ignored, like polarization, or added as an additional parameter, like the phase function P(ji n) that describes the angular distribution of scattered... 

Figure 14a. Provided the wavefront is not interrupted, it moves out uniformly in a radial direction in accordance with the accepted notion of the rectilinear propagation of light. Suppose we now have a series of plane wavefronts incident on a slit with each successive wavefront being constructed from the envelope of secondary wavelets from the preceeding wave-front as shown in Figure 14b. If the width of the slit is small relative to the wavelength of light, then the portion of the wavefront at the slit may be considered as a single Huygens source radiating in all directions to produce...

The light wave is characterized by oscillating electrical and magnetic fields.2 3 6 For propagation of light in the x direction the electric field vector E, which is customarily plotted in the y direction, is a function of the wavelength K and the time (Eq. 23-1). 

The velocity of propagation of light in a medium, c (Eq. 23-3), depends upon both e, the dielectric constant of the medium, and p, the magnetic permeability. 

Several authors [10] studied the propagation of light in a Maxwell vacuum with small nonzero conductivity and complex refractive index. By solving modified Maxwell equations, one can get the frequency-dependent speed of light, which can be associated with nonzero mass of photon. The nonzero rest mass of photon has a long history, and the astrophysical evidence is discussed in this chapter. 

Now let us consider the propagation of light pulses between a source and a detector separated by a distance r on a flat background with quantized linear perturbations. One can find easily At from the following relation ... 

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