Google have recently claimed to have achieved ‘quantum supremacy’ with a computer that completed a problem that is considered impossible for the world’s most sophisticated standard computer. While the issue of whether Google’s quantum computer, Sycamore, actually managed what they have claimed is still being debated, the news has left many asking what is quantum computing?
Quantum computers perform their calculations based on the probability of an object’s state before it’s measured, according to Science Alert. This means, while a normal computer works in binary (1s and 0s) to complete a function, the quantum computer goes beyond this and can potentially process exponentially more data than what is possible with our current technology.
In the case of Google’s computer, the paper published claimed that the task set for it, checking a random sequence of number, took the computer thee minutes and 20 seconds, according to The Guardian. By comparison, the world’s most powerful supercomputer would take 10,000 years to complete it.
The reason these computers are proposed to be faster is because they don’t use the binary system of ‘bits’ making it only possible that the state of an object is either 1 or 0. Rather, they use the quantum state of an object to produce a qubit, which can exist as both 1 and 0 simultaneously. This is called a superposition state and is kind of like the moment before a coin lands in your hand when you flip it, it exists as both heads and tales.
Scientists then plug these qubits into algorithms which solve the complex mathematical problems.
According to Live Science, Google’s quantum computer used microscopic circuits of superconducting metal to entangle 53 qubits in a superposition state. These then generated random numbers between 0 and 253 and as a result of quantum interference, some number show up more than others. When the computer measured the numbers million of times it noted a pattern.
While this achievement has been heavily discussed as to what exactly this means, almost all reportage identified that while this is a step in the right direction, the leap to making quantum computing common place is still far off in the future.