De Broin says the sculpture, called "Superficial," is about a "notion of transparency," and that:

The large stone, tucked away deep in the woods, became a reflective surface for its surroundings. In this play of splintered radiance, the rock disappears in its reflections. Because it reflects one cannot be mislead by its presence, yet we cannot seize it, rather it is the rock that reflects us.

But what about the aliens who are hiding their ship under the cloaking device? What does that have to do with reflecting me?

Here is the model De Broin used to fashion the final, large-scale sculpture. Very mecha and cool.

Michel De Broin [artist's site via Environmental Graffiti]

According to an article in the most recent issue of Physics World:

The "stealthiest" ship that currently exists is Sweden's Visby Corvette. Apart from being painted in grey dazzle camouflage and made of low-radar reflectivity materials, it also does not use propellers, which are the noisiest part of a ship. The vessel also has the lowest "magnetic signature" of any current warship.

But the next generation of warships could be truly invisible by exploiting "metamaterials" - artificially engineered structures first dreamt up by physicist John Pendry at Imperial College, London. Metamaterials are tailored to have specific electromagnetic properties not found in nature. In particular, they can bend light around an object, making it appear to an observer as though the waves have passed through empty space.

About the research, Chris Lavers writes, "If optical and radar metamaterials could be developed, they might provide a way to make a ship invisible to both human observers and radar systems, although the challenges of building a cloak big enough to hide an entire ship are huge."