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Radiation fields and hyperbolic scattering theory

Published online by Cambridge University Press:  24 October 2008

F. G. Friedlander
Affiliation:
Department of Applied Mathematics and Theoretical Physics, University of Cambridge

Extract

Let u(x, t), where x3, t, be a C solution of the wave equation on {|x| > a} × for some a > 0, and suppose that u = 0 for |x|> a, t < 0. One then also has u = 0 for |x| > a + t, t > 0, so that u(.,t) can be thought of as a wave expanding into a previously undisturbed medium. One can now ask for a description of the asymptotic behaviour of u as |x| → ∞. It turns out that there is a v0(θ, τ) ∈ C (S2 × ) such that

in the topology of C (S2 × ). This limit may be called the radiation field of the expanding wave u. (See (2) and the earlier papers quoted there.)

Type
Research Article
Copyright
Copyright © Cambridge Philosophical Society 1980

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References

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