31–40 of 135 posts
There are 20 bitcoin wallets worth more than a billion dollars each. I think it will be pretty obvious when someone gets a quantum computer working.
If Bitcoin would become vulnerable, its value would collapse to zero overnight once it's known. There is limited amount of money anyone could extract before the value collapses.
It is good that they kept the classical crypto along. However, the general tendency towards quantum-resistant cryptography leaves me puzzled. From my perspective as a physics PhD graduate, I firmly believe that a quantum computer capable of breaking public key crypto will never be built. This is because as you add more qubits, there's increased interference between them due to the additional connections required. It'…
Essentially the only reason anyone thinks that useful quantum computation is possible is because of things called threshold theorems, which state that as long as the noise in each qubit is less than some small but non-zero error rate you can add more qubits and use quantum error correction to make your computation arbitrarily precise. In other words as long as you're below the threshold rate quantum computers scale well.
Of course those threshold rates are very very small, and creating significiant numbers of qubits which are below the threshold rates is incredibly difficult, but theoretically it works.
Earlier quoted context omitted.
To a first approximation, the US government uses the same cryptography that US consumers do -- AES, SHA-2, the NIST P curves, ECDSA, etc. are all categorized for various levels of data integrity and confidentiality within the government. The same will be true of PQ signing schemes, meaning that a backdoor would be predicated on the USG believing that they have some truly remarkable NOBUS breakthrough in PQC. That fee…
> NSA interventions in cryptographic design have historically gone in the opposite direction[1]. I'm not sure I'd say that given that there are some other designs and things that have gone on[1][2]. Particularly the Dual EC debacle. They have a history of helping make suspect or down right compromised crypto if they think they can get away with it. That said it does look like they avoid doing it to anything that gets…
It is good that they kept the classical crypto along. However, the general tendency towards quantum-resistant cryptography leaves me puzzled. From my perspective as a physics PhD graduate, I firmly believe that a quantum computer capable of breaking public key crypto will never be built. This is because as you add more qubits, there's increased interference between them due to the additional connections required. It'…
I've heard physicists raise opinions like yours (i.e. QC will never be built for practical reasons), but I also hear ones that say the opposite. I'd err on the side of caution. As for your conspiracy: The conclusion of that would be to continue using hybrid constructions. Though, and I know crypto more than physics, I'd consider it as highly unlikely. Creating backdoors that others won't find is next to impossible. W…
> As for your conspiracy: The conclusion of that would be to continue using hybrid constructions.
As long as ordinary crypto does not get deprecated.
Anyway, the number of responses made me curious about this new novel crystals-kyber. Do you have any recommendations on the best introductory text that explains it from the bird's view?
It is good that they kept the classical crypto along. However, the general tendency towards quantum-resistant cryptography leaves me puzzled. From my perspective as a physics PhD graduate, I firmly believe that a quantum computer capable of breaking public key crypto will never be built. This is because as you add more qubits, there's increased interference between them due to the additional connections required. It'…
Doesn't your argument apply to classical bits too? The more interconnected a classical bit is, the more parasitic coupling it will experience. That used to be an argument used against the feasibility of classical computers in the 40s (until von Neumann published work on fault tolerant classical computing). Both classical and quantum computers (1) can not "scale" without error correction because of analog noise (altho…
It is good that they kept the classical crypto along. However, the general tendency towards quantum-resistant cryptography leaves me puzzled. From my perspective as a physics PhD graduate, I firmly believe that a quantum computer capable of breaking public key crypto will never be built. This is because as you add more qubits, there's increased interference between them due to the additional connections required. It'…
Doesn't your argument apply to classical bits too? The more interconnected a classical bit is, the more parasitic coupling it will experience. That used to be an argument used against the feasibility of classical computers in the 40s (until von Neumann published work on fault tolerant classical computing). Both classical and quantum computers (1) can not "scale" without error correction because of analog noise (altho…
This is distinct from classical computers, where you can describe a bit without needing to describe the other bits in the computer. You cannot describe a qubit (in a way that's computationally useful, at least) without describing all of them.
>PQXDH provides post-quantum forward secrecy and a form of cryptographic deniability but still relies on the hardness of the discrete log problem for mutual authentication in this revision of the protocol.
So that's why active mitm with a contemporary quantum computer is a concern mentioned in the blog post. Of course it isn't of any concern currently (since no one has the hardware to exploit this), but I'm curious why they couldn't fit the crystals-kyber method for mutual auth in this hybridized implementation? performance concerns?
There are 20 bitcoin wallets worth more than a billion dollars each. I think it will be pretty obvious when someone gets a quantum computer working.
There are 20 bitcoin wallets worth more than a billion dollars each. I think it will be pretty obvious when someone gets a quantum computer working.
Bitcoin is already quantum attack resistant, unless you use un-hashed public keys or reuse Bitcoin addresses (as some do). If Bitcoin would become vulnerable, its value would collapse to zero overnight once it's known. There is limited amount of money anyone could extract before the value collapses.
It is good that they kept the classical crypto along. However, the general tendency towards quantum-resistant cryptography leaves me puzzled. From my perspective as a physics PhD graduate, I firmly believe that a quantum computer capable of breaking public key crypto will never be built. This is because as you add more qubits, there's increased interference between them due to the additional connections required. It'…