Waves of all types inevitably spread out while propagating, owing to diffraction. Under certain strict conditions, however, waves can be made to propagate without diffraction. Although this has been ...

Proceedings of the Royal Society of London. Series A, Mathematical and Physical Sciences, Vol. 209, No. 1096 (Oct. 8, 1951), pp. 81-96 (16 pages) The radio waves from 'radio stars' may suffer ...

Diffraction phenomena are of fundamental importance for the characterization and analysis of materials in industrial and scientific applications. Prominent examples include X-ray crystallography as ...

Google Earth provides a cornucopia of exotic images of our planet taken from above. For the most part, the focus of attention is on the land and the cities, roads and natural formations that it ...