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Theorists Make Quantum Communications Breakthrough
KentuckyFC writes "One of the cornerstones of modern physics is Claude Shannon's theory of communication, which he published in 1948. If you've ever made a phone call, watched TV, or used a computer, you've got Shannon to thank for describing how information can be moved from one place in the universe to another using an idea called the channel capacity. But nobody has been able to develop a quantum version of this theory. So physicists have no idea how much quantum information can be sent from one point to another. Now two American physicists have made an important breakthrough by proving that two quantum channels with zero capacity can carry information when used together. That's interesting because it indicates that physicists may have been barking up the wrong tree with this problem: it implies that the quantum capacity of a channel does not uniquely specify its ability for transmitting quantum information (abstract). And that could be the idea that breaks the logjam in this area."
Actual link: http://cm.bell-labs.com/cm/ms/what/shannonday/paper.html
Try not to look directly at it...
You can xor a random pad of 1s and 0s with some copyrighted data, and end up with a block of data which looks totally random. Neither the random pad or the encrypted block have any useful information when taken apart, but together they contain all the information of the copyrighted work.
This is the most insightful comment ever made by AC.
I believe some mods will mod a particularly funny post as something else positive as Funny mods dont go towards the posters Karma rating.
(Now watch this get modded something crazy).
We also get news from blogs, apple fan sites, and wikileaks. Non of those is peer reviewed either. The point is that it's not that people should take articles sourcing ArXiv with a grain of salt; it's that they should take everything with a grain of salt.
If "two quantum channels with zero capacity can carry information when used together" then how much information could you send with 4 channels? Of even 2 channels with some (>0) capacity?
Would that end up with an infinite ampunt of information, or just all the information in the universe?
Maybe you'd get a 'beep' of all the messages ever sent by this method (like the beep you get from a dirac receiver in James Blish's story).
At the end of my Physics degree, I had the option of continuing in Physics academia, or going into the world of work. I'm sad to say that the main reason I wanted to leave Physics, despite somehow managing to retain a small fragment of my initial enthusiasm for the subject, was looking round at the professional physicists who took my course, and realising I really didn't want to spend the rest of my productive life surrounded by these people.
http://instantbadger.blogspot.com