Quantum computers are on the horizon, and they’ve been stuck there for quite some
time.
All the theoretical advantages they promise over classical computers, like speeding up
drug development, helping to manufacture room temperature superconductors, and cracking
encryption remain just that: theoretical.
However, a leaked paper from Google claims that for the first time a quantum computer
used its unique quantum properties to absolutely dominate a classical computer in a specific
task, demonstrating what’s known as “quantum supremacy.”
The paper was posted in September of 2019 on NASA’s website, since NASA and Google
are collaborating on the project.
Almost as suddenly as it appeared, it was taken down again.
But this is the internet, and Google of all companies should know that the internet is
forever.
The paper was copied and made widely available.
Anyone can still read it.
I read it.
A lot of it was utterly bewildering to me, a humble internet host, but I still read it
for you, dear viewer.
Luckily for me and you, actual experts in quantum computing read it too and weighed
in on what it means.
First off, they caution that it’s not yet published in a scientific journal so it may
not be the final version or even peer reviewed.
We shouldn’t get too ahead of ourselves and declare this the end of data security
as we know it, as some have been suggesting.
Experts also point out that Google’s quantum computer bested a classical computer in a
task that was tailor made to exploit the quantum computer’s strengths.
The computer was asked to simulate the outputs of a pseudo random “quantum circuit,”
basically a number generator.
I say pseudo-random because due to quantum interference, some of the numbers it generates
should have a higher probability of occurring than others.
If the quantum computer works correctly, it should produce a cluster of numbers that line
up with what we statistically expect to see.
Well surprise surprise, according to this paper the computer that uses quantum phenomena
to operate was better at predicting how quantum phenomena would generate numbers than a classical
computer.
But you may be shocked to learn just how much it stomps its supercomputer rivals.
While the Google machine churned through a million randomly generated numbers in 200
seconds, the paper estimates the most powerful supercomputer on Earth today would do the
same task, if it just had 10,000 years to do it.
Not bad for a chip with just 54 quantum bits, or qubits, one of which wasn’t working.
So if the leaked paper is to be believed, then yes, Google has demonstrated quantum
supremacy.
No one said the task the quantum computer demonstrated had to be useful for it to count.
And no one said that this means it’s time to throw our old hardware in the bin either.
Quantum computers still have a long way to go.
Namely the biggest problem with them remains errors caused by qubits decaying and losing
information stored on them.
To make what’s known as a logical qubit that’s more coherent requires hundreds or
thousands of physical qubits whose errors cancel each other out.
And a quantum computer capable of cracking encryption would require thousands of logical
qubits.
Right now the most physical qubits we’ve ever put together is 72, and that computer
was actually too difficult to control.
For quite some time it appears encrypted data will remain uncrackable.
But that doesn’t mean that Google’s demonstration of quantum supremacy in this one esoteric
task is insignificant.
This is quite a milestone that computer scientists have been working towards for decades.
If their work checks out,it will be a major step towards putting quantum computers to
work solving problems that so far have been out of reach.
Problems that really matter, like developing life saving drugs faster, or inventing new
wonder materials.
So if and when this paper gets published, let’s all act really surprised and congratulate
the researchers, okay?
Quantum computers rely on superconductors to function, which have to be kept at extremely
low temperatures.
If a quantum computer can help develop room temperature superconductors, that could be
a vital step to a quantum PC you could have at home.
If superconductors pique your interest and you want to know more about the wild possibilities
they could unlock, check out Maren’s video here.
Make sure you subscribe to Seeker to keep up to date will all your quantum news, and
as always, thanks for watching.