Finally, we calculate the number of physical qubits required to break the 256-bit elliptic curve encryption of keys in the Bitcoin network within the small available time frame in which it would actually pose a threat to do so. It would require 317 × 106 physical qubits to break the encryption within one hour using the surface code, a code cycle time of 1 μs, a reaction time of 10 μs, and a physical gate error of 10-3. To instead break the encryption within one day, it would require 13 × 106 physical qubits.
Governments are back on their anti-encryption bullshit again. Between the U.S. Senate's "EARN IT" Act, the E.U.'s slew of anti-encryption proposals, and Australia's new anti-encryption law, it's become clear that the authoritarians in office view online privacy as a threat to their existence. Normally, when the governments increase their anti-privacy sabre-rattling, technologists start talking more…
I. Taylor, and A. Turing. (2015)cite arxiv:1505.04715Comment: This update re-formats two figures to give a closer representation of the underlying text. The original paper is available from the National Archives in the UK at www.nationalarchives.gov.uk using reference number HW 25/38. 4 pages, two column format, complete text of original paper.