Quantum Supremacy summary

In 2019, Google created a quantum computer called Sycamore. It could solve, in just 200 seconds, a complex mathematical problem that would take our current fastest supercomputer 10,000 years to solve. In digital computing, the basic unit of information is a bit whereas in quantum computing, it’s a qubit. Sycamore runs on 53 qubits and, at that time, that made it the most powerful computer in the world.

But just two years later, the Quantum Innovation Institute in China claimed that their quantum computer was 100 trillion times faster than supercomputers. It ran on 113 qubits.

On November 16 of that same year, the IBM Eagle was revealed which beat them both with 127 qubits. A year later IBM launched Osprey at 433 qubits.

When a quantum computer can outperform a digital computer at a specific task, it’s known as quantum supremacy. Clearly, this point has already been reached. What’s more, we’ve only just scratched the surface of what’s possible.

There are several different ways in which quantum computing functions. Most inventors are using entangled atoms – more on that shortly – but a few researchers have found a way to send information on light beams using a clunky mirror-based setup. The race is on to be the first to optimize this technology. But we’re still many years away from a functioning quantum computer that can solve real-world problems in fields ranging from medicine to fuel to cybersecurity.

Even so, the age of silicon appears to be coming to an end. Moore’s Law, first postulated in 1965, suggests that the number of transistors that can be built into a microchip doubles every 18 months. Effectively, that means computer power also doubles every 18 months. But if we continue primarily using silicon, this law will stop being true in the very near future.

You see, digital computers are reaching their capacity to be able to solve large-scale problems – or at least to be able to solve them quickly enough to be useful. But quantum computers can take us into a new era with their insanely fast speeds and ability to simultaneously analyze multiple paths and problems to create the best solution.

So what is it that makes quantum computers so powerful? Well, two key factors contribute to this power.

The first is superposition, or the ability of an atom to exist in multiple states at the same time. This is how quantum computers can solve problems so quickly – by analyzing all paths at the same time to determine the path of least action.

The second factor is known as entanglement. This is when two atoms establish interaction with each other, sharing information, and keep that connection even when they’re separated at a great distance.

Now, you’re probably already wondering, How do I get my hands on one of these quantum computers? Why isn’t all technology already based on quantum computing? Well, the problem is that there’s one primary challenge, and it has to do with something called coherence.

For quantum computers to work, a system has to be completely stable. Atoms are fragile and the least disturbance disrupts them. So quantum computers as they currently exist have to be framed in systems that keep them at absolute zero temperatures.

There’s hope, though. Mother nature achieves coherence at regular temperatures in a little process called photosynthesis. So scientists are studying how coherence is achieved in nature in the hope of finding a way to recreate the process in a computer.

But before we talk about the practical applications of quantum computers, let’s take a quick look back at how we got here.