Researchers in China claim to have achieved quantum supremacy, the point at which quantum computers accomplish tasks that are almost impossible for classical computers to perform. The device, named Jiuzhang, reportedly performs a calculation in 200 seconds that will take a regular supercomputer 2.5 billion years to complete.
Traditional computers process data as binary bits – either zero or one. Quantum computers, on the other hand, have different advantages because the bits can also be one and zero at the same time. It increases potential processing power exponentially, since two quantum bits (qubits) can be in four possible statuses, three qubits can be in eight statuses, and so on.
That means quantum computers can explore many possibilities simultaneously, while classical computers have to run each option one after the other. Advances so far have seen quantum computers perform calculations much faster than traditional one, but their last test was when they could do things that classical computers couldn’t. And the milestone was dubbed “quantum supremacy”.
Last year, Google was the first to claim to have cracked quantum supremacy. The company said the 53-qubit Sycamore processor had performed certain computing in 200 seconds – a task Google predicted would take on the world’s most powerful supercomputer in 10,000 years.
And now China claims to have joined the quantum supremacy club. Jiuzhang’s computer reportedly found a solution to a very challenging problem in three minutes and 20 seconds. Traditional supercomputers, on the other hand, will take no less than 2.5 billion years to do the same – for reference, it’s more than half the age of the Earth today.
The calculation is what is known as the sampling boson, which calculates the output of a complex optical circuit. Basically, photons are sent to the system through a lot of input, and once inside, the photons are separated by file breakers and reflected by mirrors. Boson sampling takes into account all these variables and calculates the possible output of this maze – a very difficult task for ordinary computers, but a good test for quantum computers.
In this case, Jiuzhang works with 50 photons, 100 inputs, 100 outputs, 300 file breakers and 75 mirrors. The computer managed to calculate the distribution sample in the time it took to make the coffee, while Sunway TaihuLight – currently the fourth most powerful supercomputer in the world – would need a fifth of the entire age of the universe to do the same. Job.
That’s obviously a big achievement, but that doesn’t mean that traditional computers are going nowhere anytime soon. This type of calculation itself is not very useful – it is largely a test to show off the potential power of quantum computers. In addition, they still have some stability issues that need to be addressed, and are not necessarily better at everything than their predecessors.