refractin’ back atcha

A few of my Povray scenes include objects with negative indices of refraction; I’ve said of this one that three-quarters of it cannot exist in the real world. Now I read in The Economist that, because a negative-refractive slab could make a “perfect lens” (for obscure reasons), there’s an active effort on to create such a chimera; indeed the effect has been demonstrated but only with microwaves.