Chaos, like next year’s weather, is anything but predictable. So
results appearing in the 8 October print issue of PRL may seem
paradoxical: researchers claim that for the first time, two
lasers have been synchronized so that one can anticipate the
chaotic fluctuations in the other. Some experts are skeptical of
the result, but it illustrates some of the challenges in the
field of chaos research, where physicists are attempting to
understand and make use of nature’s seeming disorder. The
weather is a classic example of chaos. In a perfect world, a
computer–given a complete set of atmospheric data and
equations–should be able to crunch out forecasts for years to
come. But in practice, tiny uncertainties in the initial data
set eventually lead to completely inaccurate predictions. A
laser also becomes very unpredictable if you reflect a small
portion of the laser’s output back into the device. This
feedback makes the laser’s future output–like next year’s
weather–strongly dependent on its past. Alan Shore and h