Serious quantum computers are finally here. What are we going to do with them? - MIT Technology Review
Another reason for caution is that it isn’t obvious how useful even a perfectly functioning quantum computer would be. It doesn’t simply speed up any task you throw at it; in fact, for many calculations, it would actually be slower than classical machines. Only a handful of algorithms have so far been devised where a quantum computer would clearly have an edge.
Thu Apr 26 11:18:16 2018 - permalink -
Many common cryptographic schemes rely on the fact that this [finding the prime factors of an integer] is hard for a conventional computer to do. But cryptography could adapt, creating new kinds of codes that don’t rely on factorization.
This is why, even as they near the 50-qubit milestone, IBM’s own researchers are keen to dispel the hype around it.
(...) it may be possible to get valuable results from an error-prone quantum machine paired with a classical computer.
“We don’t really know what the equivalent of ‘Hello, world’ is on a quantum computer.”