Invisibility device close to being invented, or just a paper theory?

Two mathematicians have boldly gone where no boffin has
gone before and described the theoretical possibility of a
cloaking device, the BBC reports.

However, before the Trekkies among you don your Romulan
cozzies and rush for a copy of the Royal Society
publication in which Nicolae Nicorovici and Graeme Milton
expound their cloak of invisibility, be aware it's very
much a paper concept, currently applicable only to small
objects of a particular range of shapes.

The theory is based on "anomalous localised resonance" -
analogous to the effect by which a vibrating tuning fork
placed close to a wine glass will cause the latter to
vibrate, as the Beeb notes. Nicorovici and Milton say an
illuminated speck of dust (yup, that's the scale we're
talking about), in close proximity to a "superlens*"
cloaking material, would "scatter light at frequencies
that induce a strong, finely tuned resonance in a cloaking
material placed very close by". Said resonance cancels out
the light coming from the speck, and voila! -
invisibility.

At least, that's the plan. Superlens pioneer Sir John
Pendry, of Imperial College London, said of the
mathematicians' admission that "the cloaking effect works
only at certain frequencies of light, so that some objects
placed near the cloak might only partially disappear": "I
believe their claims about the speck of dust and a certain
class of objects. In the paper, they do give an instance
about a particular shape of material they can't cloak. So
they can't cloak everything."

He further explained: "Providing the specks of dust are
within the cloaked area, the effect will happen. A cloak
that only fits one particular set of circumstances is very
restrictive - you can't redesign the furniture without
redesigning the cloak."

Accordingly, we don't think Starfleet Command will be
losing any sleep over this one just yet.

Nicorovici and Milton's research is published in the
Proceedings of the Royal Society A: Mathematical, Physical
and Engineering Sciences. ®