This is huge: Physicists have figured out how to reliably transmit quantum information, a major first step toward the kind of quantum communications and quantum computing that would dramatically enhance our ability to secure networks, crack codes, and search databases.
These potential applications of quantum computing—and I'll get to what exactly that means in just a minute—help explain why government agencies ought to be interested in such technologies. And the latest news in this realm is significant. It comes from a team of nanoscience researchers at the Delft University of Technology in the Netherlands, where physicists successfully transmitted encoded quantum information from one computer chip to another, across a distance of about 10 feet.
This stuff is complex, but it gets easier from here: In classical computing, basic units of information are assigned values of either 1 or 0. But in quantum computing, the basic units of information, qubits, don't have set values. This distinction makes qubits more dynamic—they can do more stuff!—but it also makes qubits harder to transport reliably. And once scientists figure out how to do so, the future of quantum computing and quantum communications really comes into focus.
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"In the whole field of quantum information, there are two different directions: One is quantum computing and the other is quantum communications," said physicist Steve Rolston, who is co-director of the Joint Quantum Institute at the University of Maryland. "If we start with quantum computing, this is the holy grail... The quantum computer is not just a faster regular computer. So far we've only identified a few problems that it's really good at: crunching numbers—which sounds like an arbitrary math problem, but that's how cryptography works—and searching databases."
In other words, a quantum computer is only exceptionally good at a few things—but those few things happen to have major implications for the future of intelligence, surveillance, and security. "That's why the NSA in particular is so interested in quantum computers and would like to have one, and probably would not tell anyone if they did," Rolston told me.
There's some debate over how advanced quantum computing already is. The Canadian startup D-Wave claims to have built a $15 million quantum computer, though many scientists have expressed skepticism about the technology. It still piqued the interest of Google, NASA and the Universities Space Research Association, which teamed up last year to install a D-Wave device in a NASA lab so that researchers can come by and test how it might advance machine learning. Earlier this year D-Wave's CEO was in Washington, D.C., shopping around his company's wares.
Quantum computing's code-cracking potential could undermine encryption protocols that now secure information across any number of networks—the kinds used by financial institutions, government agencies, etc. Quantum computing could also process enormous databases like no computer today.
But quantum communications represents "sort of the flip side," Rolston says. "Because of the laws of quantum mechanics, you can develop ways to communicate with people that are provably secure. It doesn't mean that people can't listen in, but it means you would be able to tell." Here's why: There's this rule in quantum mechanics called the No-Cloning Theorem. Rolston explained it to me like this: "Basically, what that says, is you cannot make an exact copy of an unknown quantum state."