Anomalous Reeections near a Caustic
نویسندگان
چکیده
Waves propagating in a medium with highly variable refractive index tend to focus forming caustics. The energy content of the waveeeld in the vicinity of a caustic is higher than that of the ambient eld away from the caustic. Consequently, waves scattering from heterogeneities located near caustics have more energy than a eld scattering a little further away from the caustic. For a suitable choice of Sobolev norms for the domain and range spaces of the scattering operator, the restriction to scatterers supported away from caustics is a bounded operator, whereas the restriction to scatterers supported in a neighbourhood of caustics is unbounded.
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