A lesson in logic needed?
I just came across an unusual article about quantum cryptography. The article's headline was "Quantum Cryptography Theory Has a Demonstrated Security Defect." This certainly sounds like something worth reading more about, but if you skip ahead to the bottom of the article you find that researchers just found a flaw in a published proof:
Consequently, Yuen's theory is correct, and at present there is no theoretical proof of the unconditional security for any QKD.
So they didn't really show that quantum cryptography has a demonstrated security defect. Instead, they just showed that there's a flaw in one particular proof of the security of quantum cryptography. The two aren't really logically equivalent, are they?