John Smith

computer science, quantum computing, and cryptocurrency. The future of crypto is #QuantumResistant

[John Smith @JSmith_Crypto]

I've recently noticed an uptick in claims of "quantum resistance" from cryptocurrency projects. This thread explains how to differentiate which are BS and which are legit.

[John Smith @JSmith_Crypto]

@Shin0xAkuma @BTCJSON1 @BTCBYCKO That’s not a stupid question at all!

Here’s a thread summarizing how that would work and what the challenges would be:

https://t.co/PgFyv0p0Cf

[John Smith @JSmith_Crypto]

SOLUTION #2: Bitcoin adds a quantum-resistant signature & holders proactively migrate.

How well this works will depend on:
>How long is the time-window for safe migration? (It would ideally begin years in advance)
>How proactively & universally do BTC holders comply? 10/

[John Smith @JSmith_Crypto]

@farming_shrimp @dp608 @julianhosp Re: that amount of time

https://t.co/eyGybMCLxO

[John Smith @JSmith_Crypto]

How long until someone builds a quantum computer that can steal BTC by quickly deriving private keys from their associated public keys?

Serious estimates range from 5 to 30+ years, with the median expert opinion being around 15 years. 3/

[John Smith @JSmith_Crypto]

@Scamdevlous @loomdart I wrote up a summary of the nature of the threat and potential solutions here, if you’re curious:
https://t.co/H00QCbH3K6

[John Smith @JSmith_Crypto]

Thread explaining the future threat to #Bitcoin from #QuantumComputing -- How big a deal is it really? What is the timeline? And how do the Bitcoin devs plan to deal with it?

[John Smith @JSmith_Crypto]

@BELMG4 (a QC capable of that feat in particular, I mean)

[John Smith @JSmith_Crypto]

@BELMG4 We are still in the “literally 0% chance that such a device exists” era, for now.

[John Smith @JSmith_Crypto]

@0x_ff0 He clearly understands the risks that the presence of a QC would entail (far better than most), but authored and advocated for Taproot in spite of that. Which is what Casarin was expressing his misgivings about in the original quote.

[John Smith @JSmith_Crypto]

@haydentiff no

[John Smith @JSmith_Crypto]

There is *extreme* skepticism about quantum computing among the most senior Bitcoin developers.

From reading and listening to their opinions on it, they mostly believe it either isn't possible at all or won't be a real threat until after they're dead.

[John Smith @JSmith_Crypto]

A frank assessment of where we are right now with Bitcoin and quantum computing from a Bitcoin core developer.

[John Smith @JSmith_Crypto]

@blk014 @QRLedger thanks! 👀

[John Smith @JSmith_Crypto]

@wholesum @real_or_random *wipes brow*

https://t.co/rpnGfRFuh8

[John Smith @JSmith_Crypto]

@wholesum @real_or_random Thanks for the heads up, I’ll keep an eye on what Tim and the other expert cryptographers have to say about this going forward

[John Smith @JSmith_Crypto]

@KonstantHacker @luke9971 Relevant

https://t.co/H00QCbpsSy

[John Smith @JSmith_Crypto]

Thread explaining the future threat to #Bitcoin from #QuantumComputing -- How big a deal is it really? What is the timeline? And how do the Bitcoin devs plan to deal with it?

[John Smith @JSmith_Crypto]

@Ahmed_Elbecha @danheld This thread outlines the main challenges and solutions the Bitcoin devs have discussed.

https://t.co/H00QCbpsSy

[John Smith @JSmith_Crypto]

Thread explaining the future threat to #Bitcoin from #QuantumComputing -- How big a deal is it really? What is the timeline? And how do the Bitcoin devs plan to deal with it?

[John Smith @JSmith_Crypto]

@jlizakowski @mcclure111 Sorry about the spam. This thread goes over all the ways Bitcoin devs have discussed dealing with the problem. Take care.

https://t.co/kCtB8DokqG

[John Smith @JSmith_Crypto]

So let’s go over the major challenges & their solutions.

We can separate vulnerable BTC into three classes:
1) Lost coins (several million)
2) Non-lost coins held in reused/taproot/otherwise-vulnerable addresses
3) Coins in the mempool (i.e., being transacted) 5/

[John Smith @JSmith_Crypto]

@strobist @PrestonPysh Median expert opinion is that the threat is around 15 years away, according to a survey conducted late last year. The attached thread discusses the main challenges for BTC and their solutions.

Really sorry about the reply spam.

https://t.co/Nolft2F59W

[John Smith @JSmith_Crypto]

How long until someone builds a quantum computer that can steal BTC by quickly deriving private keys from their associated public keys?

Serious estimates range from 5 to 30+ years, with the median expert opinion being around 15 years. 3/

[John Smith @JSmith_Crypto]

@jlizakowski QCs are used for more than cracking codes.

[John Smith @JSmith_Crypto]

The best case scenario for #Bitcoin with quantum computing:
>QC progress is slow and public
>A quantum-resistant signature is added years ahead of any real risk
>Large majority of BTC migrate during that period
>Community accepts burning all ECDSA coins without major controversy

[John Smith @JSmith_Crypto]

@NateGeraci @Tanzeel_Akhtar Deep learning ETF

[John Smith @JSmith_Crypto]

@Trentw Mainly the reason Pieter articulates in the attachment here.

https://t.co/iYA5tunnkd

[John Smith @JSmith_Crypto]

SOLUTION #1: preemptively burn lost coins via soft fork

How well this works will depend on:
>Are enough lost coins covered to prevent a liquidity crunch or market spook?
>Which coins get burned, who decides, & how difficult is it to reach consensus on these decisions? 7/