2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/164729We carefully examine the negative refractive index slab perfect lens theory by Pendry and point out an inconsistency that can be resolved. As a result, we find negative index slabs do not amplify or enhance evanescent waves and therefore they do not make a perfect lens in the sense that was originally suggested.submission to PRLOpticstext