Photon-based quantum computer out calculates supercomputer.

[sjastro]

In fact the supercomputer failed to find the solution as it is estimated it would require 2.5 billion years of computer time.
By comparison the photon based quantum computer took 200 seconds.
Physicists in China challenge Google’s ‘quantum advantage’

......But the calculation in this case is a ‘#P-hard problem’, which is even harder than notoriously tricky NP-hard problems, for which the number of solutions increases exponentially with the number of variables......

To understand what a P and NP problem is this video will prove useful.

 

[FrumiousBandersnatch]

It's a step forward, but as I understand it, this quantum computer is configured to solve only one particular problem; it's not yet general-purpose even for quantum computing problems.

 

[sjastro]

It's a step forward, but as I understand it, this quantum computer is configured to solve only one particular problem; it's not yet general-purpose even for quantum computing problems.

Progress occurs in small steps.
What was significant about this experiment it was run at room temperature.
Qubits based on electrons or atoms require temperatures barely above absolute zero to counter quantum decoherence.

 

[FrumiousBandersnatch]

What was significant about this experiment it was run at room temperature.

Yes, that's well worth emphasising.