A story appeared on Forbes today claiming that we now have an absolutely unbreakable cipher. It cites a paper published in Nature Communications. However, I'm skeptical:
But what if there were a method of enabling data to be sent using an "absolutely unbreakable" one-time communication technique? What if that technique could achieve perfect secrecy cryptography via correlated mixing of chaotic waves in an irreversible time-varying silicon chip?
That seems like a lot of buzzwords and doesn't sound convincing.
With no software or code to manipulate, traditional methods of cracking computer encryption are irrelevant
Again, Dr. Cruz reiterated that there is no code to manipulate, and the limited software is ROM based, so traditional methods of hacking encryption are irrelevant.
Don't ciphers and their weaknesses exist independent of software and code? Solitaire has neither software nor code, but has weaknesses.
The cryptographic keys generated by the chip, which are used to unlock each message, are never stored
You need the keys to decrypt the message, so even if they're never stored, something good enough to reconstruct them must necessarily be stored.
It is claimed that even facing an attacker with "unlimited" technological power, even if they could access the system and copy the chips, would be unable to break the encryption because it is protected by the second law of thermodynamics and the "exponential sensitivity of chaos."
I really don't like the sound of this.
Professor Andrea di Falco of the School of Physics and Astronomy at the University of St. Andrews, another author of the study, said that "this new technique is absolutely unbreakable, as we rigorously demonstrated in our article."
A really extraordinary claim.
The second law of thermodynamics prevents this attack. Every time Alice and Bob change the chip with an irreversible process, they increase the total entropy of the system and the environment, creating new chaotic structures exponentially different from the ones used in the communication (conditions 3 and 4). If Eve accesses the system, it is impossible to recreate the initial chips and to perform any search, as this requires reverting the transformation of Alice and Bob with an entropy decrease, thus violating the second law.
This is contrary to my understanding of the second law of thermodynamics. Can't you easily decrease entropy in systems that aren't closed (such as the chips), just by increasing it more outside the system (exhaust heat somewhere)?
So is this new cryptosystem legit, or is it just more snake oil? If it's legit, then what are the explanations for my above concerns? If it's snake oil, how did it manage to dupe both Nature Communications and Forbes?
Did anyone wish for crypto woowoo for Christmas?
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