New Property of Light Discovered (phys.org) 81
A team of researchers affiliated with several institutions in Spain and the U.S. has announced that they have discovered a new property of light -- self-torque. Their findings have been published in the journal Science. Phys.Org reports: Scientists have long known about such properties of light as wavelength. More recently, researchers have found that light can also be twisted, a property called angular momentum. Beams with highly structured angular momentum are said to have orbital angular momentum (OAM), and are called vortex beams. They appear as a helix surrounding a common center, and when they strike a flat surface, they appear as doughnut-shaped. In this new effort, the researchers were working with OAM beams when they found the light behaving in a way that had never been seen before.
The experiments involved firing two lasers at a cloud of argon gasâ"doing so forced the beams to overlap, and they joined and were emitted as a single beam from the other side of the argon cloud. The result was a type of vortex beam. The researchers then wondered what would happen if the lasers had different orbital angular momentum and if they were slightly out of sync. This resulted in a beam that looked like a corkscrew with a gradually changing twist. And when the beam struck a flat surface, it looked like a crescent moon. The researchers noted that looked at another way, a single photon at the front of the beam was orbiting around its center more slowly than a photon at the back of the beam. The researchers promptly dubbed the new property self-torque -- and not only is it a newly discovered property of light, it is also one that has never even been predicted. Their technique may be used to modulate the orbital angular momentum of light in ways very similar to modulating frequencies in communications equipment, leading to the development of novel devices that make use of manipulating extremely tiny materials.
The experiments involved firing two lasers at a cloud of argon gasâ"doing so forced the beams to overlap, and they joined and were emitted as a single beam from the other side of the argon cloud. The result was a type of vortex beam. The researchers then wondered what would happen if the lasers had different orbital angular momentum and if they were slightly out of sync. This resulted in a beam that looked like a corkscrew with a gradually changing twist. And when the beam struck a flat surface, it looked like a crescent moon. The researchers noted that looked at another way, a single photon at the front of the beam was orbiting around its center more slowly than a photon at the back of the beam. The researchers promptly dubbed the new property self-torque -- and not only is it a newly discovered property of light, it is also one that has never even been predicted. Their technique may be used to modulate the orbital angular momentum of light in ways very similar to modulating frequencies in communications equipment, leading to the development of novel devices that make use of manipulating extremely tiny materials.
Re: Can self-torque enable faster-than-light trav (Score:1)
I mean they're not wrong, per se. If you got light to travel faster faster than light it'd still be traveling at the speed of light, what with it being literally (in the literal sense) light. Weird shit might happen if it's possible, and I'd like to know if it is as well, but it is definitionally impossible for light to actually travel "faster than light."
Why? Scalar Waves ALREADY do... apk (Score:1)
Why? Scalar Waves ALREADY do: "Heresy" you say?? Look into them & the work of Nikola Tesla (IF not the bosnian pyramids sending them even now - that's right - it's BEEN tested).
* :)
APK
P.S.=> Plus, LASTLY, on a "theoretical note" (since I'm not a physicist I MAY need 'correction'): Tachyons TECHNICALLY do also assuming Einstein is correct that when you approach the speed of light, time slows OR ceases - given that. since tachyons MOVE BACKWARD IN TIME (proven by experiments)? They are FTL already too.
Weaponizeable . . . ? (Score:3)
The researchers then wondered what would happen if the lasers had different orbital angular momentum and if they were slightly out of sync. This resulted in a beam that looked like a corkscrew with a gradually changing twist.
So wake me up when this technology is weaponizeable, and I can laser corkscrew those pesky neighborhood kids on my front lawn.
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Light sabers and hard-light holograms, here we come!
Not news (Score:2)
Since QM was discovered people have known that light could carry a quadupole moment in each photon. Largely we ignore this. It does have some amazing uses but the problem is generating it is hard and not having it get split by interactions to keep it in that state.
Wow. (Score:3)
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No joke. They could at least write a little code to change smart quotes into ASCII ones. Or a replace filter to fix that particular UTF8 string. Jesus humping monkeys, how do these people get out of bed without a robot nanny.
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Nah, I like that feature. It's always funnier watching some guy try to prove he's smarter than everybody else when all his posts are constantly corrupted with odd characters, making him look dumb.
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A hesitancy to accept at face value the claims of young grad students rapidly speaking in highly technical language to describe novel techniques in the field of quantum mechanics is typical enough...
But sparing readers on a public forum any basis for your opinion with an excuse of not wishing to "prejudice" anyone is the sort of kindness used to excuse the "soft" bigotry of any ch
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The physicist girls are hot, is that what you mean? And smarter than me. You know what that means: makes me hot. I will leave it to someone of the appropriate orientation to opine on the male physicists.
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The physicist girls are hot, is that what you mean? And smarter than me. You know what that means: makes me hot. I will leave it to someone of the appropriate orientation to opine on the male physicists.
I see, modded down by someone with a smooth spot where genitals used to be.
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Light isn't supposed to interact with itself according to current models.
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Correct, a photon can interact with itself, but light, as in "lots of photons", does not. Well, there are loopholes, such as pair production, where a photon transforms into something else that can interact with another photon, but the original photon is lost in this case, so it never actually interacted.
Should have called it... (Score:2)
Special Beam Cannon
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Wave motion gun
Breaking news: Light is a narcissist (Score:1)
It likes to torque about itself!
Nooooooo! (Score:1)
firing two lasers at a cloud of argon gas doing so forced the beams to overlap, ...
Egon: Don’t cross the streams.
Peter: Why?
Egon: It would be bad.
Peter: I’m fuzzy on the whole good/bad thing. What do you mean “bad”?
Egon: Try to imagine all life as you know it stopping instantaneously and every molecule in your body exploding at the speed of light.
Raymond: Total protonic reversal.
Peter: That’s bad. Okay. Alright, important safety tip, thanks Egon.
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Jillian: Girl power!
Erin: Yeah girl power!
Abby: Men are bad!
Patty: You said it girl!
Same old twist (Score:3)
Interesting but useless.
https://journals.plos.org/plos... [plos.org]
Re:Round and round. (Score:4, Informative)
Good old AC -- this sounds to you a little bit like something you had heard of involving light, and so conclude it must be exactly this other thing, without bothering to learn the least little thing about the actual experiment. Optical vortexes are quite explicitly not related to circular polarization and is due to the physical structure of the beam (it is not homogeneous or symmetric).
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Good old AC -- this sounds to you a little bit like something you had heard of involving light, and so conclude it must be exactly this other thing, without bothering to learn the least little thing about the actual experiment. Optical vortexes are quite explicitly not related to circular polarization and is due to the physical structure of the beam (it is not homogeneous or symmetric).
appreciate the heads-up on the distinction. it's the mention of self-torque that's most interesting. i believe you may be off-base with the homogenity: the gas cloud apparently does something to align the beams.
ido kaminer's team showed that phase-coherent beams can *literally* be made to bend round corners. as in, the progression of the phased-array as it bends, every component bends by the *same* amount. fascinatingly, the phase of every component rotates by half the angle of the "bend".
whether self-t
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Both angular momentum and spin are rotational properties of light, but not quite the same thing.
paper available at arxiv (Score:5, Informative)
the full paper is available here:
https://arxiv.org/abs/1901.109... [arxiv.org]
personally i am delighted that this has been experimentally observed, because for the particle physics theory i've been working on for 36 years, it's an essential requirement that light have self-torque. imagine what would happen if a multi-beam of phase-coherent light was created and did the "curvy" thing. now imagine if that "curve" is so tight that, actually, the beam goes in a full circle (this is not new: it has been explored by Ido Kaminer and his team) and if the beam goes in a full circle, it's a phase-coherent multi-beam *with itself*... now you have a particle.
https://arxiv.org/search/?sear... [arxiv.org]
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shape-preserving circular trajectory "non-paraxial" phase-coherent accelerating beams:
https://arxiv.org/abs/1201.030... [arxiv.org]
ye gods what a load of buzzwords :)
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You know, strip out the tech crap and you're describing a donut... literally n wavelengths of resonance doing the circular waddle.
Phase coherent... yep.
With itselfs? yep
Litterally an F2 is oscillating left right left right, taking 2 F oscillations to do the loop, ... sounds very familiar....
oh look, that sounds very much like spin 1/2! gosh, who would have thunk it...
the fascinating bit is that you only need the one photon, in each particle, because its radiation (at the speed of light, duh) creates an EM field that interacts... with itself (thanks to superposition and the self-torque thing) on each loop. next loop: interacts with itself and itself+itself, next loop: interacts with itself+itself+itself, now you have a pascal's triangle.
ta-daaa, you have a really simple way to think of the vi
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So line "self-torque -- and not only is it a newly discovered property of light, it is also one that has never even been predicted." is a load of bollocks then?
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So line "self-torque -- and not only is it a newly discovered property of light, it is also one that has never even been predicted." is a load of bollocks then?
predicted by the self-proclaimed "peer-reviewed academics".... yeah. what's old is new, and what's new is old... the mandala effect eats its own bottom, just like the yellow submarine... :)
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They crossed the beams (Score:2)
I told you crossing the beams would be bad.
Perhaps more data over fiber now? (Score:1)
Weighing Light (Score:1)
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