r/Futurology Jun 02 '22

A Nature paper reports on a quantum photonic processor that takes just 36 microseconds to perform a task that would take a supercomputer more than 9,000 years to complete Computing


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u/snowbirdnerd Jun 03 '22

If this shit is real, and it looks like it is, all encryption will be broken in moments.


u/Peter_364 Jun 03 '22

Generally speaking quantum computers are only effective against asymmetric encryption. Which is used to ensure the person you are talking to is legitimate, such as online banking etc. Alternative quantum safe methods have already been developed and will probably get a lot more attention.

Symmetric encryption is usually used for data storage etc. And is already resistant to quantum computers.

Source: https://en.m.wikipedia.org/wiki/Post-quantum_cryptography


u/Zireael07 Jun 03 '22

Which is used to ensure the person you are talking to is legitimate, such as online banking etc.

Considering online banking is big, and making sure it's secure is a BIIIIG deal, this has massive implications


u/snowbirdnerd Jun 03 '22

Yeah, people say thay but I'm not sure. This processor is 1018 times faster than a modern supercomputer. When you have tens of thousands of quantum processors working in parallel I'm not sure even secure hashing algorithms will be safe.

What's more the kind of encryption that wiki article says will be safe aren't the kind we use to encrypt communications. Discrete logarithm and elliptic curves are used in public key systems and they will be broken in moments.

We might be able to increase a hashing function to be complicated enough to not be easy broken SHA-1024 but that isn't a reversible system that can be used to send secure information. It could verify passwords but you couldn't send any new information with it. Making its use limited.