The Quantum Issue: Letter From The Editor

Quantum this, quantum that…who put a stupid cat on-chain!?

Ahem. 

Alright, let’s be serious. The threat that a viable, actually functioning, quantum computer would pose to Bitcoin if it were to be built is very serious. It is the concrete example of an existential threat, in every sense of the word. 

One of the bedrock foundations that Bitcoin rests upon is the assumption of a functioning cryptographic system that can be used to produce unforgeable signatures, i.e. that if you follow that system’s protocol properly when signing things, there is no way that anyone but a bitcoin’s rightful owner could produce a signature needed to spend it unless the rightful owner failed to secure their private key from theft. 

Quantum computers toss that right out the window. There goes the integrity of the entire mechanism that is used for owners of bitcoin to authenticate their ownership for the protocol to process their legitimately authorized transactions, and ONLY their legitimately authorized transactions. There’s no way for anyone to actually own anything in the context of the Bitcoin protocol if that assumption breaks. 

Bitcoin breaks if that assumption breaks. 

Thankfully, there are many different cryptographic systems that exist, and not all of them rest on assumptions that a quantum computer breaks. That’s the good news. The bad news is that its all a set of tradeoffs, none of them are ideal, and there are going to be some hard choices that have to be made. 

But there are solutions to just about every one of the problems that a viable quantum computer would create…except the problem of choosing which solutions to use. So in light of that, here is The Quantum Issue. 

This issue is a lot more structured than most past issues, and that is to ensure that it guides a reader through the entirety of the problem space and solution space without assuming any prior understanding (this is a very deep and technical subject). 

The first set of articles goes through the general issue of quantum computing itself, how it differs from classical computing, why that matters, how likely it is one is developed soon, etc.

The second set examines Bitcoin’s exposure. How is it exposed? How badly is it exposed? How can that degree of exposure change? 

The third set examines concrete (or developed enough to not be too hard to get to a concrete place) solutions to securing your bitcoin in a quantum safe way, and handling a network wide migration to those solutions. 

Don’t miss your chance to own The Quantum Issue — featuring articles written by many influential figures in the space working on the necessary pieces for a post-quantum Bitcoin!

This piece is the Letter from the Editor featured in the latest Print edition of Bitcoin Magazine, The Quantum Issue. We’re sharing it here as an early look at the ideas explored throughout the full issue.