Mutual Interference And Structural Properties of Object Images in the Vicinity of the Gravitational Lens Cusp Point

Scalings for diffraction-decorated caustics in gravitational lensing

“…(spacings in table 1)/Z. Such decoherence is one reason why interference in lensing has not yet been observed; it has been extensively studied, for example in the papers already cited [6,7,9,11,[19][20][21][22]. And of course, the size of the aperture of the telescope directed at the source is also a limiting factor; I have not discussed this here, apart from briefly at the end of section 2 (see also [37]).…”

“…Especially significant near caustics are the effects of decoherence caused by the finite size of sources [19][20][21]. Most works have considered decoherence near fold caustics, but the stronger cusp singularity has also been studied [22]. On astronomically relevant scales, the associated diffraction integrals are highly oscillatory, raising challenges for their numerical evaluation; an important recent advance, especially for multidimensional integrals, has been the development and application of sophisticated contour deformation techniques [23,24].…”