This lab at IBM
plex molecule ever modeled with
a quantum system. Ultimately,
researchers might use quantum
computers to design more e;cient
solar cells, more effective drugs,
or catalysts that turn sunlight into
Those goals are a long way o;.
But, Gambetta says, it may be possible to get valuable results from
an error-prone quantum machine
paired with a classical computer.
From a physicist’s dream
to an engineer’s nightmare
“The thing driving the hype is the
realization that quantum computing
is actually real,” says Isaac Chuang, a
lean, soft-spoken MIT professor. “It
is no longer a physicist’s dream—it
is an engineer’s nightmare.”
Chuang led the development
of some of the earliest quantum
computers, working at IBM in
Almaden, California, during the
late 1990s and early 2000s. Though
he is no longer working on them, he
thinks we are at the beginning of
something very big—that quantum
computing will eventually even play
a role in artificial intelligence.
But he also suspects that the
revolution will not really begin
until a new generation of students
and hackers get to play with practi-
cal machines. Quantum computers
require not just di;erent program-
ming languages but a fundamen-
tally di;erent way of thinking about
what programming is. As Gambetta
puts it: “We don’t really know what
the equivalent of ‘Hello, world’ is on
a quantum computer.”
We are beginning to find out. In
2016 IBM connected a small quan-
tum computer to the cloud. Using a
programming tool kit called QISket,
you can run simple programs on it;
thousands of people, from academic
researchers to schoolkids, have built
QISket programs that run basic
quantum algorithms. Now Google
and other companies are also put-
ting their nascent quantum comput-
ers online. You can’t do much with
them, but at least they give people
outside the leading labs a taste of
what may be coming.
The startup community is also
getting excited. A short while after
seeing IBM’s quantum computer, I
went to the University of Toronto’s
business school to sit in on a pitch
competition for quantum startups.
Teams of entrepreneurs nervously
got up and presented their ideas
to a group of professors and inves-
tors. One company hoped to use
quantum computers to model the
financial markets. Another planned
to have them design new proteins.
Yet another wanted to build more
advanced AI systems. What went
unacknowledged in the room was
that each team was proposing a
business built on a technology so
revolutionary that it barely exists.
Few seemed daunted by that fact.
This enthusiasm could sour if
the first quantum computers are
slow to find a practical use. The best
guess from those who truly know
the di;culties—people like Bennett
and Chuang—is that the first use-
ful machines are still several years
away. And that’s assuming the prob-
lem of managing and manipulating
a large collection of qubits won’t
ultimately prove intractable.
Still, the experts hold out hope.
When I asked him what the world
might be like when my two-year-old son grows up, Chuang, who
learned to use computers by playing with microchips, responded
with a grin. “Maybe your kid will
have a kit for building a quantum
computer,” he said.
Will Knight is senior editor for AI.