Spectral Changes Induced by Scattering From Space-Time Fluctuations

  • Emil Wolf


In the majority of theoretical studies dealing with the scattering of electromagnetic waves on random media one assumes that the incident field is monochromatic and that the density fluctuations of the medium may be described by equilibrium thermodynamics. In the last few years it was found that when these restrictions are removed, a number of interesting new phenomena are revealed. In this talk a review of these developments is presented. In particular an account is given of several recent investigations regarding spectral changes produced by scattering of light of any state of coherence and polarization and with arbitrary spectrum on a medium whose response is random both in space and in time, but is statistically homogeneous, isotropic and stationary, at least in the wide sense. It is shown that the spectrum of the radiation may be shifted towards the longer or towards the shorter wavelengths by the scattering process, thus inducing redshifts or blueshifts of spectral lines;2 and moreover, that conditions may be found which ensure that these shifts imitate the Doppler effect in its essential features, even though the source of the radiation, the scatterer and the observer are all at rest relative to each other.3,4 This possibility is of particular interest for astronomy.5


  1. 1.
    E. Wolf and J.T. Foley, “Scattering of electromagnetic fields of any state of coherence from space-time fluctuations”, Phys. Rev. A 40:579–587 (1989).ADSCrossRefGoogle Scholar
  2. 2.
    J.T. Foley and E. Wolf, “Frequency shifts of spectral lines generated by scattering from space-time fluctuations”, Phys. Rev. A. 40:588–598 (1989).ADSCrossRefGoogle Scholar
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    E. Wolf, “Correlation-induced Doppler-like frequency shifts of spectral lines”, Phys. Rev. Lett. 63:2220–2223 (1989).ADSCrossRefGoogle Scholar
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    D.F.V. James and E. Wolf, “Doppler-like frequency shifts generated by dynamic scattering”, Phys. Letts. A. 146:167–171 (1990).ADSCrossRefGoogle Scholar
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    D.F.V. James, M. P. Savedoff and E. Wolf, “Shifts of spectral lines caused by scattering from fluctuating random media”, Astrophys. J. 359:67–71 (1990); see also E. Wolf, “Non-cosmological redshifts of spectral lines”, Nature 326:363–365 (1987).ADSCrossRefGoogle Scholar
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    E. Wolf, J.T. Foley and F. Gori, “Frequency shifts of spectral lines produced by scattering from spatially random media”, J. Opt. Soc. Amer. A. 6:1142–1149 (1989); ibid 7:173 (1990).ADSCrossRefGoogle Scholar
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    A. Lagendijk, “Terrestrial redshift from a diffuse light source”, Phys. Letts. A 147:389–392 (1990).ADSCrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media New York 1991

Authors and Affiliations

  • Emil Wolf
    • 1
  1. 1.Department of Physics and AstronomyUniversity of RochesterRochesterUSA

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