With a computing power that no one could dream of a few years ago, quantum computers put traditional cryptography in check.
Cryptocurrencies and the blockchain are secure because they use complex algorithms to generate them, and encryption based on computer networks.
But cryptography is a slave to technological evolution. An encryption algorithm can be broken by brute force, although it would take thousands of years of calculations with conventional computers. Experts have long wondered: What if quantum computers were tried?
In 2019 Google presented Sycamore, a 54 qubit quantum computer, capable of performing in 200 seconds a calculation for which the most powerful traditional computer of the moment would take 10,000 years.
A quantum computer works at the atomic level, managing the states of the atoms, which can be at the same time a 0 or a 1. This breaks the paradigm of traditional computing, and opens up a new world of possibilities.
The unit of power of a quantum computer is the qubit or qubit. In 2019, Google’s quantum computer reached 57 qubits.
Just a few days ago, IBM unveiled its 127-qubit Eagle quantum computer. And it announces that in 2023 they will reach 1,121 qubits.
Next to it, Google’s 57-qubit computer will look like a ZX Spectrum.
IBM has said that Eagle cannot be equaled even with all the computers on Earth put together: it would take more bits than there are atoms adding up all the human beings on the planet. And that brings us to cryptocurrencies.
Most cryptos, including Bitcoin, are based on the Blockchain, the chain of encrypted data that maintains a network made up of dozens of thousands of computers. All Bitcoins mining, buying and selling operations must be approved by 51% of the computers on the network.
That is why it is so difficult to hack: no hacker has enough computational power to hack or replace 51% of the computers in a Blockchain network, except for a quantum computer.
Another weak point is the cryptographic keys. In each operation, a public key is generated from the private and secret key of the owner of each cryptocurrency.
Guessing a private key from a public one would require thousands of years of calculations with conventional computers and seconds, or a few minutes, with a quantum computer. And there are already computers of this type in private hands.
As Business Insider tells us, expert Divesh Aggarwal, a researcher at the National University of Singapore, predicted in 2017 that quantum computers would be poised to break the cryptography of cryptocurrencies, “within a decade.”
A few days ago another scientist, Jian-Wei Pan, creator of a 66 qubit quantum computer, stated through El Confidencial that there are barely 3 or 4 years left for this prediction to come true.
We have used cryptocurrencies as an example, but the threat extends to all cryptographic keys: the mobile password, the router password, the bank account password.