Quantum Computers cannot break Bitcoin

Bruce Schneier reports:

Researchers have calculated the quantum computer size necessary to break 256-bit elliptic curve public-key cryptography:

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.

In other words: no time soon. Not even remotely soon. IBM’s largest ever superconducting quantum computer is 127 physical qubits.

That IBM devide doesn't really have even a single qubit. It just has a quantum experiment that can be simulated with 127 qubits.

It appears that Bitcoin will be safe for centuries, from these attacks. A more likely outcome is that Bitcoin will be banned as a waste of electricity, and because its main function is to facillitate extortion, contraband, and money laundering.

Now that Russia is being bloccked from SWIFT international banking, I wonder if it will sell oil for bitcoin. That could increase demand for bitcoin.

People in the USA and Canada have also been cut off from banking services for political reasons. The bitcoin advocates would presumably say that this underscores the need for a nonpolitical currency.

The International Congress of Mathematicians was planning its big once-every-four-years meeting in St. Petersberg this summer. It is now boycotting Russia and holding the meeting online. This is an unfortunate politization of Mathematics. St. Petersburg is a long way from Ukraine. There were previous meetings in Peking and Moscow, in spite of the Communist governments.

The current Nature magazine podcast:

Almost everything we do on the Internet is made possible by cryptographic algorithms, which scramble our data to protect our privacy. However, this privacy could be under threat. If quantum computers reach their potential these machines could crack current encryption systems — leaving our online data vulnerable.

To limit the damage of this so called 'Q-day', researchers are racing to develop new cryptographic systems, capable of withstanding a quantum attack.

This is an audio version of our feature: The race to save the Internet from quantum hackers

It says:

Researchers estimate that to break cryptosystems, quantum computers will need to have in the order of 1,000 times more computing components (qubits) than they currently do.

It will require a million times more.

Update: Here is the Twitter account of the Russians trying to hold a math conference. They are not supporting the Ukraine invasion, and just want a great math conference. It is too bad that the Russia haters are destroying it.