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Stenner and co-workers have compared the speed of information in a "superluminal" medium (dashed lines) and a vacuum (solid lines). A "0" was represented by a rapid drop in intensity just before t = 0 ns, while a "1" was represented by a sudden 50% increase in intensity. If we compare how, say, a "0" travels through both media we find that the front of the pulse, which is smooth, arrives earlier (i.e. more to the left) when it travels through the superluminal medium. However, the abrupt change in intensity that denotes the "0" arrives at the same time in both media. The same is true of information bit "1". In other words, information about whether the pulse carries a "0" or a "1" does not arrive faster than light.