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EM waves have frequency and polarization and phase. Their "orbital angular momentum" is some combination of these parameters so you can't increase bandwidth over what can be done using some combination of these.
Actually, I don't think their OAM is a combination of those parameters. It's about the spatial distribution of the phase around the axis of transmission.
It's using the spatial variation of the signal. In cylindrical coordinates (r,theta,z) aligned with the axis of transmission z, it uses different phases at different thetas. In particular, a bunch of superposed signals each with phase varying around the z axis as cos(i*theta) for i=0,1,2,... should stay conveniently distinct from transmitter to receiver.
I think the axis of transmission is baked into the idea pretty deeply - it's inherently unidirectional. I also think it's not robust to superposition: another such bunch of signals passing obliquely across the receiver would mess everything up.
The Prius Lane Keep Assist feature does steer a bit, gently - the wheel tends to drift toward it's best guess of the center of the lane. It won't drive for you, though: if you take your hands off the wheel it notices (I think it notices the absence of any applied torque over some reasonably short interval), sounds an alarm and turns off the feature.
"Images may not be copied or offloaded, and the images and their texts may not be published. All digital images of the Oxyrhynchus Papyri are © Imaging Papyri Project, University of Oxford. The papyri themselves are owned by the Egypt Exploration Society, London. All rights reserved."
They want help transcribing these documents, but don't want anyone to keep copies of the images? How rude.
The article says they're stopping production of the roadster to focus on the S. It says nothing about anything failing.
Heart rate monitors can and have been used in PE classes to grade students on their exertion rather than their capabilities. In stereotypes: the idea is to reward the nerd busting his ass rather than the jock breezing through, even though the jock might jog faster than the nerd can run.