There is something missing...
I am disappointed with the lack of sharks in this article. El Reg you can do better than that. :)
Boffins build laser that can twist its own light
The world has known that information can be encoded on “twisted light” for some time, but only with complex equipment. Now, boffins from South Africa have demonstrated a laser that can add the twist at its output. The Register will resist the temptation to call this some kind of game-changer, but it's a useful development, …
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Wednesday 16th March 2016 16:02 GMT PNGuinn
Re: Sharks
But .. But... The sharks will get terribly dizzy.
Cue much legal shenaniganification by the likes of PETA and the RSPCA.
It'll never do.
On the other hand, putting a nice twist on the light - will that mean that the light will now travel in a straight line for a bit longer? Like a rifle bullet?
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Wednesday 16th March 2016 10:51 GMT Schultz
Use quantum physics language for photons ...
Bam, you got 'new science'. (New, as in: nobody ever heard it before).
Use the old-fashioned language of "polarization" and "interference" -- and the new science doesn't sound so new anymore. It's a good thing that the physical reality doesn't really care about your language, so go ahead and spin your photons into new orbits as much as you care. Just make sure they don't get too dizzy, it would be a pity if they fall over.
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Thursday 17th March 2016 09:05 GMT Schultz
Some nerdy comments for Graham Dawson
You can exhaustively describe light by defining it's location (3D in space), impulse (--> propagation through space) and polarization (field vector perpendicular to the propagation direction).
To create "Orbital Angular Momentum" (OAM), scientists use a spatial polarization mask to obtain "geometric phase control" (see Nature article). So they play with polarization and impose different polarization properties on different spatial parts of the beam. They didn't create some magic new photon property of OAM, but they just play with location dependent polarization.
All OAM stories I read about make a big deal about the potential applications in data transfer (multiplexing the throughput of an optical a fiber via OAM control). But fibers only transmit a limited number of modes (let's call those OAM states) -- if you increase the number of transmitted modes by using a multimode fiber (bigger diameter), you'll always have increased signal degradation and loss, so the total information you can physically transmit does not scale proportionally to the number transmitted modes.
I'd be very happy if those OAM people would come up with some magic to improve data transmission, but I just don't see the physics working out for them.
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Wednesday 16th March 2016 16:44 GMT Tikimon
Shark-safe laser deployment
You simply mix some old analog tech with new quantum-ish tech. Mount TWO lasers on the sharks' heads, which apply spin in opposite directions. This cancels the torque and returns the shark to a stable weapons platform.
Although one wonders if spinning the sharks would stabilize their path through the water? Could this be more useful than detrimental?
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Wednesday 16th March 2016 18:14 GMT Robert Helpmann??
Re: Shark-safe laser deployment
You simply mix some old analog tech with new quantum-ish tech.
It is not "quantum-ish" as lasers depend on quantum effects to generate light. And water? What you meant to say was "propelled by rockets into a volcano." And yes, two lasers are better than one. Keep going with that plan.
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Thursday 17th March 2016 16:07 GMT Schultz
Re: Momentum? Does light have mass then?
Photons have no rest-mass. But then they always move with the speed of light and never exist at rest. So that's all right.
Einstein derived that the mass m is given by: E = m*c**2; m = E/c**2, with energy E and speed of light c.
The impulse p was described by deBroglie: λ = h/p; p = h/λ, with the Planck constant h and wavelength λ.
Put them together and you get E = hν = hc/λ, with frequency ν -- another fundamental equation of physics.
Biting the hand that feeds IT
