'White Holes' — Black holes are suddenly so last century

In the March 7, 2008 issue of Science magazine physicists reported that "... blue-shifting is a feature of the event horizon of a white hole — an inside-out black hole," according to JR Minkel writing in the latest issue (May, 2008) of Scientific American.

Here's the abstract of the Science article.

Fiber-Optical Analog of the Event Horizon

The physics at the event horizon resembles the behavior of waves in moving media. Horizons are formed where the local speed of the medium exceeds the wave velocity. We used ultrashort pulses in microstructured optical fibers to demonstrate the formation of an artificial event horizon in optics. We observed a classical optical effect: the blue-shifting of light at a white-hole horizon. We also showed by theoretical calculations that such a system is capable of probing the quantum effects of horizons, in particular Hawking radiation.

...................

In the same issue of Science, Adrian Cho summarized the work, writing, "Using an optical fiber and laser light, physicists have simulated a "white hole" — essentially a black hole working in reverse. The model might soon mimic the "Hawking radiation" predicted to emanate from black holes."