Based on ray tracing approach, light propagation in inhomogeneous media with fluctuating coefficient of refraction n = n (r) can be interpreted as a chaotic mixing of the wavefront in the 6-dimensional phase space where the spatial coordinates are complemented by the respective wave vector components. According to ray tracing, the evolution of wave vectors follows Hamiltonian dynamics and hence, according to the Liouville’s theorem, the mixing of the wave front takes place in an incompressible flow field. We use this approach to show that the brightest light speckles in inhomogeneous media follow a power law intensity distribution, and to derive the relevant scaling exponents.
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