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Comment Re:Strap your Buick to the backyard windmill.... (Score 1) 650

The real questions is, where will the energy come from? What energy source will be used to generate all of that additional electricity that our power grids will require? In North America we already have important segments of the power grid that are under supplied during peak load[...]

Hmm, haven't kept up much, huh. Electric cars can save the grid, not drive it into the ground. The current electric grid has issues at peak loading. Electric cars don't have to charge at peak loading times, in fact, they can deliver energy back to the grid at peak loading times. Google is even into this with grid monitoring software demos . I, of course, wonder how you can keep hackers from emptying your batteries...

Comment Re:Other than supposed security improvements... (Score 5, Interesting) 131

no cloning principle are exactly right. You cannot read and then reemit a photon with the same polarization
Hmm. I think you meant you cannot read and reemit with 100% fidelity. http://www.icfo.es/images/publications/J05-055.pdf, "Quantum Cloning", Valerio Scarani, Sofyan Iblisdir, and Nicolas Gisin. This is a late 2005 review and of eavesdropping techniques for QKD. Much of the terminology of quantum physics is unfamiliar to me but I think the paper states that Eve could theoretically get 5/6 of the bits through cloning and to keep this from happening, Alice and Bob have to assume an eavesdropper if more than 11% of the bits have errors. When dealing with single photons, read errors will happen. There is also work at the University of Tokyo, the Japan Science and Technology Agency, and the University of York (Sam Braunstein and Akira Furusawa) on telecloning (combined quantum teleportation and quantum cloning) that I have a reference to an experiment done two years ago where they cloned 58% of the photons successfully out of a theoretical 66%.

Others have created quantum crypto systems that take the possibility of cloning into account, http://w3.antd.nist.gov/pubs/Mink-SPIE-One-Time-Pad-6244_22.pdf

'basic' quantum cryptography that is taught can be hacked
This is true but I think not for the reasons you believe. Basic quantum crypto provides confidentiality only. To keep from being hacked, you must provide authentication as well (Alice must be able to prove she is communicating with Bob and not Eve). I haven't heard of a way to do this without falling back onto more conventional cryptographic techniques such as RSA signatures - at least when doing quantum crypto over fiber. Maybe sending photons through the atmosphere means you can actually just see if somebody is acting as a man-in-the-middle.

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