Part 2 mentions two quantum algorithms that could be used to break Bitcoin (and SSH and SSL/TLS; and most modern cryptographic security systems):
Shor's algorithm for factorization and Grover's search algorithm.
I don't know what heading I'd suggest for something about how concentration of quantum capabilities will create dangerous asymmetry. (That is why we need post-quantum ("quantum resistant") hash, signature, and encryption algorithms in the near future.)
Part 2: http://davidbkemp.github.io/QuantumComputingArticle/part2.ht...
Shor's algorithm: https://en.wikipedia.org/wiki/Shor%27s_algorithm
Grover's algorithm: https://en.wikipedia.org/wiki/Grover%27s_algorithm
I don't know what heading I'd suggest for something about how concentration of quantum capabilities will create dangerous asymmetry. (That is why we need post-quantum ("quantum resistant") hash, signature, and encryption algorithms in the near future.)