Peeter Saari
Abstract
Presented is an overview of electromagnetic versions of the so-called X-type waves intensively studied since their invention in early 1990.-ies in ultrasonics. These waves may be extremely localized both laterally and longitudinally and - what has been considered as most startling - propagate superluminally without apparent spread. Spotlighted are the issues of the relativistic causality, variety of mathematical description and possibilities of practical applications of the waves.