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Biological Lasers
MancunianMaskMan writes "Sharks in the seas all around the world are interested in this story,
though the less scientifically-minded will read the summary on the beeb web site about laser light produced by a living cell. The technique starts by engineering a cell that can produce a light-emitting protein that was first obtained from glowing jellyfish."
The laser/shark meme is really boring and pathetic. Can't people move on?
"the less scientifically-minded will read the summary on the beeb website..."
Slashdot viewers are more than capable of understanding the paper, but that doesn't mean we want to pay for something we're most likely not going to implement in our basements when we get a spare chance.
In addition, laser beam eyes would be cool at night.
Not really all that cool, considering you would be effectively blind while using them.
Cyclops' eyes shoot crimson rays of kinetic force. I believe you're thinking of Kryptonians.
It's a laser when coherent wavelength light is emitted. I.e. all the same frequency, going in the same direction.
Okay, cool, we've used transgenic techniques to give other organisms bioluminescence; now tell me how you make that coherent. (No, I didn't read the article.)
From what I can gather of TFA, the cell isn't really a laser per se, as much as it is a cell that, genetically engineered to express GFP, can survive and be observed while be used as part of the lasing medium in a GFP-based organic dye laser(which is stimulated by blue light from outside the tube in which the cell(s) and the GFP dye fluid are placed).
That is pretty cool, and I suspect that there will be some very elegant live-cell imaging that comes out of applications of this technique; but it leaves me wondering how small a complete biological laser could be: ie. something that both expresses the proteins needed to make up the lasing medium and uses some flavor of bioluminescence to pump its own lasing medium...
I'm not enough of a photonics guy to tell you exactly where the cut-off between "light coming from florescent materials that have been made stimulated by sufficiently energetic light to re-emit at their wavelength of choice(which is usually what people playing with GFP are observing)" and "a dye laser, having been pumped by an outside light source, successfully lasing(which is apparently what is happening here)"; but ruling out bioluminescence should be pretty simple: GFP is, while conveniently florescent in a very distinctive color, not luminescent. It only glows when energized by sufficiently energetic outside light sources(blue or UV typically). The cellular chemistry behind bioluminescence involves a whole different set of chemicals, and one assumes that the scientists wouldn't have started with a bacterial species that possesses those.
Even if they did, since the dye chamber had to be externally pumped to lase, one could simply observe it in the dark in order to establish a baseline of any native luminescence before observing it while it is being pumped.
So, towards engineering a shark with lasers, it seems that one needs:
(a) this "GFP" protein as a gain medium,
(b) mirrors,
(c) this "blue light" to bathe it in, and
(d) some sort of lens(?)
what is interesting, it is that all of the above components can easily be made by nature. GFP is already there, the "blue light" could come from a similar process, lenses are in eyes so I would guess (b) could be the hardest one to come up with, but there are numerous animals with a silver-ish tint (reflective surface) plus several wasp species that have so much metal in their stings (deposited there trace by trace from their diet) that they can easily drill into seeds. Point being that reflective (i.e. metal) components can be intermingled and arrayed into living tissue.
I keep wondering as to what could be the chances of such a "laser organ" evolving naturally? Can the fact that it hasn't be seen as a hint that evolution does not have a plan, and is merely a sum of random events? And let's speculate even further- what use could such an organ have?
The three laws of thermodynamics:(1) You can't win. (2) You can't break even. (3) You can't even quit.
If you could accurately target the eyes, I suspect that things could get a good deal more practical. Lasers of disturbingly low power can leave you with permanent blind spots, and ones lower still can leave you with dazzling after-images for quite some time...
Why not instead of a weapon,actual eyes. You can do lots of fun things when you mix lasers with sensors, like phase shift sensitivity, chirped pulse ranging, LIDAR, etc.