Seems to me that a lot of Hollywood science fiction writers are given physics jobs at the navy. If all goes well then the Austin Martin in the movie Die another day could soon be a reality. Wars throughout the twentieth century prompted advances in stealth technologies. Some of the earliest but most significant strides towards invisibility involved covering ships with flamboyant cubist patterns – a technique known as "dazzle painting". During the Second World War, the US military even worked out a way of using lights to make the brightness of a ship match that of the background sea. Radar was born. For ships to dodge radar, both a ship's geometry and a ship's coating have to be considered. Radars are particularly receptive to right angles, which is why modern battleships are often peculiarly shaped. Special paint and foam-coating have also been used to cover ships, which convert radio-waves into heat and stop radio waves being reflected, rendering the signals useless. 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.

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