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Twisted Light Spins Out

If you were pinning the hopes of your next startup on last year’s announcement of twisted light communications  you might want to scale back you venture capital search drastically, or if you’re far enough along, hurry up and cash the check. Last year, a team of scientists claimed that they had made the first transmission modulating the orbital angular momentum of light.  They claimed that by modulating different whole integer values of lights spin, they could provide much broader communications bandwidth  than what was currently available.  Their scientific report appeared in Nature, and subsequently on the BBC new service as well as other media outlets.

Since then, it has been shown, (see the references), that the newly proposed mode of propagation, at least in free space, can’t bee sustained and does not offer bandwidth improvements over existing communication methods such as multiple in multiple out, (MIMO).  One study even showed that some of the claims made for the method contradict the second law of thermodynamics.

While large media splashes were made about the initial reports of OAM technology demonstrations, I can’t find a single mention of the contradicting studies in any of the major media outlets.  This brings up the question of responsibility in scientific journalism.  How far should the popular scientific press be expected to go to make the public aware of counter views to, or disputes of science and technology they’ve reported on?  I know there are a number of new scientific developments every day, and it would probably be impossible to track the progress of each development.  However, in one case this would seem to be an invalid excuse.  The comment stream at the end of the Scientific American report actually contains a link to one of the contradicting studies.

For big splash articles like those linked to below in Scientific American, the BBC, and Nature, should the public expect their news sources to update them on developments instead of leaving them ignorant by omission?

References:

Encoding many channels on the same frequency through radio vorticity: first experimental test

http://iopscience.iop.org/1367-2630/14/3/033001/article

doi:10.1088/1367-2630/14/3/033001

BBC Report on Twisted Light

BBC:  ‘Twisted’ waves could boost capacity of wi-fi and TV

Nature:Terabit free-space data transmission employing orbital angular momentum multiplexing
doi:10.1038/nphoton.2012.138

Scientific American: Twisted Radio Waves Could Expand Bandwidth for Mobile Phones

Is orbital angular momentum (OAM) based radiocommunication an unexploited area?

Comment on ‘Encoding many channels on the same frequency through radio vorticity: first experimental test’

doi:10.1088/1367-2630/14/11/118001

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