Semiconductors slow light

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In a universe subject to the laws of evolution, it may seems open to question whether anything stays the same forever, "forever" being the sort of length of time during which evolution tends to play a trick or two. Having said this, the speed at which light likes to zip around (299,792,458 m/186,281 mi per second through empty space) is a good bet for a permanent feature of whatever the universe will be in the future.
This, of course, does not mean that light cannot travel more slowly. Researchers at Imperial College (London) have just found out how you can actually slow it down. Pass light through a layer of wafer-thin films of semiconductors, and you can make it travel at less than 1/40th of its speed in empty space. They hope to bring it to a complete standstill. This would perhaps satisfy Faust, and his desire for that unique, suspended moment when one could say "halt, you are beautiful". It also means that you can finally travel faster than (slowed down) light. Of course, being able to control the speed of light is excellent news for any future optical ICT.

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