Written as editor of the New Statesman’s NS Tech and first published here.
Remember when Canadian PM Justin Trudeau batted right out of the park the suggestion from a reporter that he might not understand quantum computing?
Yeah, his simple explanation was pretty impressive on the fly, but we wanted to find out a bit more about what quantum computing really is – and what it isn’t.
Luckily, IBM has just launched a cloud-based platform so anyone can try quantum computing.
NS Tech caught up with Dr. Andreas Fuhrer, quantum scientist at IBM’s Research in Zurich, to talk about the facts and the legends surrounding this new technology.
That thing Justin describes is called ‘quantum parallelism’
So we all know that classical computer bits are either 0 or 1, on or off, current or no current. Well, the ‘quantum parallelism’ of qubits means they can hold many states at the same time.
“Imagine – a classical bit is planet like earth – 0 would be the south pole and 1 would be north,” Fuhrer explains.
“With a quantum bit, you can be everywhere. The number of configurations is much, much larger. They’re not physically smaller – it’s just quantum bits can hold much more information.”
You can’t touch a qubit
Trouble with qubits is, if you try to measure one to see what state it’s in, it loses its information.
You can, technically, touch them. Indeed a single, tiny qubit will fit right in your hand at about a third of a millimetre. But you shouldn’t. It’s broken the moment you do.
“For that not to happen – we’ve had to create a scheme that can correct for errors – and to do that, IBM is working on a five qubit basic unit,” he says.
“Four of those qubits contain information – but the central one is used just to measure the parity – checking whether all of them are in the same state. We don’t actually measure the state, just the error.”
In fact, if you touched it right now, you’d probably die
“That’s one of the reasons why they have to be at very low temperature in an extremely protected environment,” Fuhrer says.
“IBM’s qubits are kept at -273 degrees celsius – absolute zero – inside a really big, five-layer thermos.”
The scientists there manipulate the qubits using electric signals. So, it won’t replace your laptop, unless you have an appetite for cold.
But it is definitely better at some stuff than a computer
If you put together IBM’s 5 qubit units to make a 100 qubit system you would need a computer the size of the universe to hold that same data processing power.
“There are some applications where we already know a quantum computer would be exponentially faster than a classical computer,” he explains.
“There are certain problems in nature at microscopic scales – individual molecules and atoms – where you can’t currently describe what’s happening exactly, you rely on approximations.
“Using a quantum computer you could emulate and learn something about novel molecules, which will aid in drug and materials discovery.”
But it’s really not the computer to end all computers. “It will be able to tackle some of the problems it’s difficult to tackle with a classical computer, and faster, but some would be cheaper to still do with a classical computer,” he adds.
So, it won’t be your next laptop – will you ever get to use one?
Yes and no. The experience will be not unlike using a super-computer today – a cloud-based service, accessed over the internet. You’ll add your calculation to a queue, then get an email when it’s done and the results are ready to be retrieved.
But even in five to 10 years, the system would still fill a small room. So why all the noise around quantum computing if most of us will never use it?
“There are several reasons why we wanted to open our platform up to the public,” Fuhrer explains.
“A lot of people don’t know what it is, think it’s mysterious or unclear, but have heard it’s emerging. Now people have a place where they can play around with a real system.
“That could be educational institutions, particularly for those who are exploring careers as quantum scientists.
“Also small companies that could deliver a product to be used by quantum scientists or uses quantum technology.
“We hope to foster a community of people that are active in this field – to spark new ideas that use quantum in the market.”
If you fancy yourself as the next Dr. Andreas Fuhrer, or even if you’re more of a Justin Trudeau, you can head to IBM’s Quantum Experience right now, from the comfort of your own home.