Contrasting string holography to its optical namesake
  We assess the prospects of using metamaterials for simulating various aspects of analogue gravity and holographic correspondence. Albeit requiring a careful engineering of the dielectric media, some hallmark features reminiscent of the hypothetical 'generalized holographic conjecture' can be detected by measuring non-local optical field correlations. The possibility of such simulated behavior might also shed light on the true origin of those apparent holography-like phenomena in the condensed matter systems with emergent effective metrics which may not, in fact, require any references to the string-theoretical holography. 
D. V. Khveshchenko
cond-mat.str-el gr-qc hep-th