The big quantum buzzword these days is "quantum supremacy." (It's a term I despise, even as I acknowledge that the concept has some utility. I will explain in a moment). Unfortunately, this means that some researchers have focused on quantum supremacy as an end in itself, building useless devices to get there.
Now, optical quantum computers have joined the club with a painstakingly configured device that doesn’t quite manage to demonstrate quantum supremacy. But before we get to the news, let's delve into the world of quantum supremacy.
The quest for quantum supremacy
"Quantum supremacy" boils down to a failure of mathematics, combined with a fear that the well will run dry before we’ve drunk our fill.
Source: Ars Technica