cryptking

Join us tomorrow for the next Official QRL Show Live with special guest Hunter Beast. Hunter (@cryptoquick) is a leading Rust/Bitcoin developer and the author of BIP360- Pay to Quantum-Resistant Hash (P2QRH). As quantum risk continues to progress, there's a lot for us to cover at the intersection of Bitcoin and post-quantum security 🔐 🗓️ When: Wednesday- April 15th ⏰ Time: 11 AM ET (15:00 UTC) Here's the link below to bookmark. See you there 👇 youtube.com/live/0PoTq0kWV…

Finally had the time to carefully read the details of the QSB method by @avihu28 from @StarkWareLtd. The tl;dr: The three proposals on the table -- QSB, LFC, and BIP360 -- are not mutually exclusive, and none of them is rendered obsolete by the other two. I want to explain where they overlap and where they don't. My bottom line is that all three approaches can, and possibly should, be implemented together. Hopefully, I got everything right. [ If you don't know what LFC is, I don't blame you. It's a rather new proposal by @roasbeef, based on a protocol by @or_sattath and me called Lifted FawkesCoin. The Beef does not call it that way, but it doesn't seem that they named it at all, so I'll keep calling it LFC. Our paper: eprint.iacr.org/2023/362 Beef's proposal: x.com/roasbeef/statu… ] Since Avihu's proposal was posted a couple of days ago, I've seen a barrage of posts lauding it for "making Bitcoin post-quantum secure", some even arguing that it proves Bitcoin "launched post-quantum" (lol). While QSB definitely adds a new and important tool to the post-quantum toolbox, it is a far cry from how the superlative posts present it, which caused some people, myself included, to be concerned that the hype might overshadow other important post-quantum efforts. Ever since OP, I've seen Avihu and @EliBenSasson doing their best to dispel this misconception and put this work in the right scope. But after the horses have left the stable, this is often as futile as plugging a dike with your thumb while trying not to mix metaphors. One way I can help is to bring forward an important existing problem that QSB does not address and describe a specific effort to address it. I'm hopeful that this helps frame QSB correctly, and makes the discussion more constructive. The important problem I am talking about is dealing with laggards/procrastinators: people who did not prepare for q-day in any way (be it because they lost their keys, were convinced that quantum computers are "just a hype", took a very long nap, etc.). QSB does not help laggards (nor was it intended to), while LFC is primarily focused on helping laggards. On the other hand, the key drawback of QSB is that generating the required auxiliary data is very expensive. Estimated at $100s of dollars per txn. These costs cannot be reduced as they don't arise from a challenging and complicated computation, but from an important proof-of-work puzzle. Another small disadvantage is that QSB is based on Taprootesque hacks that some people in the community are scheming to patch away. In particular, BIP110 will completely decimate QSB. iiuc, if BIP110 is rolled out, it might cause all UTXOs generated by QSB to become indefinitely unspendable (unless it includes some designated failsafe), though I'm not too sure about that. Advantages of LFC over QSB: - Helps laggards. With LFC you can quantum-safely spend a huge subset of currently existing UTXOs, including any address generated by an HD wallet after 2014. Depending on the chosen mode of operation, LFC can even help recover wallets with lost secret-keys (this particular mode of operation is called permissive LFC and, unlike other modes, it requires a hard-fork and not just a soft-fork). - Applies to all the cases QSB applies to, but much cheaper to use, and does not require any pre-q-day preparations. - Transactions are cheaper and quicker to generate by magnitudes. Disadvantages of LFC over QSB: - requires a fork. Moreover, the fork is beyond a simple OP_CODE implementation and adds complexity to the protocol on both the user and miner sides. - Delegates some of the stuff Bitcoin/QSB secures cryptographically to economic incentives (though nothing that allows theft, more of a "one side can misbehave and cause both sides to lose" kind of situation, and even that in a limited sense, without any emergent prisoner's dilemma). - Has a bit of a complicated UX. Each spend is a two-phase process. - Confirmation time is quite high, ranging from hours to days, as the security relies on sufficient temporal separation between the two phases All in all, there are three important proposals for quantum-proofing: 1. BIP360 (h/t @cryptoquick): fork for adding support for pq-sigs. Cost of use: marginal. 2. LFC: fork for post-quantum spending from pre-quantum UTXOs without preparation. Cost of use: noticeable. You need to generate a zk proof that is a bit on the heavy side, nothing your computer can't handle, but might be an obstruction for hardware wallets, etc. 3. QSB: requires no fork but is highly expensive to use, $100s of computation per transaction. Does not help laggards. I think these three proposals complement each other nicely: QSB can be used to quantum-proof large sums as early as today, making sure they are safely spendable after q-day, even if no fork is deployed. BIP360 will provide pq-signatures, while LFC will provide a safe migration route for laggards. If pq-signatures are noticeably more expensive to use due to their increased size, LFC can also serve as a "slow but cheap" alternative, with transactions about the same size as they are now (in some cases, even a bit smaller!), but with slower confirmations.

@IgorKruglov12 @WarPath2pt0 @cguida6 Science points to a creator. Especially modern science like quantum fisics and such. If everything that is not observed exists in a state of superposition, only collapsing into measurable reality once observed, who was the first observer before life showd up?