As the title notes, I've a question or two about Quantum Communications, or more specifically, their perceived security. China recently sent an experimental quantum communications satellite into orbit and is receiving signals from it. It's being billed as "hack proof", but is it really? From what I know and have looked into, Quantum communications have been "hacked": http://www.popsci.com/technology/ar...ck-quantum-encryption-scheme-leaving-no-trace http://www.techrepublic.com/blog/it...ptography-works-and-by-the-way-its-breakable/ http://arstechnica.com/science/2011...-cryptography-by-faking-quantum-entanglement/ http://www.wired.com/2013/06/quantum-cryptography-hack/ They are more secure, but not unbreakable so that much is likely hyperbole on the part of an overzealous, and ever ignorant media. But adding to this, there are way to guess the encryption keep with a 5/6 fidelity, meaning the key is basically broken - this is called the imperfect Cloning, which, though the No-Cloning Theorem states no perfect key can be reproduced, can create an imperfect key that is so similar that the missing pieces can be uncovered without much effort. Another problem is that while the communications themselves may be encrypted by quantum trickery, they can't be read in the same state. They must be converted into plain text, and any plain text, such as this post on AMF, can be intercepted, read or altered. With that said, my questions are these. Is this unhackable or hyperbole? What methods could an adversary leverage to break or negate the effectiveness of quantum encryption and communications? Are the methods of breaking quantum encryption, if true, such as high powered lasers, practical? Is this Chinese satellite actually the first of its kind? Or have others, perhaps smaller CubeSats been placed into orbit to study the same effects?