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Scientists Invent World's First Anti-Laser
Velcroman1 writes "Two scientists at Yale University have built the laser's first doppelganger: the anti-laser. While a conventional laser emits a constant beam of light in one direction, the anti-laser simply does the opposite. It takes that same steady light stream and interacts with it in such a way that it absorbs and cancels out the light. And scientists hope the strange creation could help the fight against cancer. A. Douglas Stone, one of the two researchers behind the project, said he came up with the idea for a 'nega-laser' when working with equations for a random laser with his partner in crime, Hui Cao. 'I figured, if we just somehow illuminated the cavity, and replaced the gain medium with something that tends to absorb light, we could essentially reverse the process,' Stone said. Oh, that makes sense."
All they really needed to say was that it's the time-reversed counterpart of a laser. Calling it an "anti-laser" makes it sound like it shoots out a beam of darkness or something like that (which could be cool, but physically impossible).
Why this is neat is that, because it's the reverse of a laser, it'll absorb some frequencies almost perfectly while ignoring others. The reason why they said this would work for cancer, for instance, is that you could embed some of these dudes in the cancer (there's techniques for that, I have no idea how they work) and then bombard them with a laser frequency that normally passes harmlessly through humans. Areas without these reverse-lasers will be unaffected, but areas with them will get really hot, killing the cancer. We use similar techniques already (with I think gold, I'm not quite sure) in order to localize radiotherapy, but I believe that the radiation used in the current methods still kills a lot of normal cells on its own.
You win. Mods, please get the parent to +5 Informative. It's clearly the best post on the story.
"I zero-index my hamsters" - Willtor (147206)
Um "A doppelgänger (pronounced [dplg] ( listen)) is a tangible double of a living person in fiction, folklore, and popular culture that typically represents evil. In the vernacular, the word doppelgänger has come to refer (as in German "doppelt(e)") to any double or look-alike of a person." from your link right there it clearly is being used in the "evil twin" sense
If these guys have come up with something that will scale up to megawatt powers, this could spell the end of overhead power lines. It could power anything line-of-sight, including satellites. It could also transmit solar power harvested from space to the earth. Laser light can be focused tightly onto a target, unlike microwaves or radio-based radiation. This could be very efficient...