Computing revolutions are surprisingly rare. Despite the extraordinary technological progress that separates the first general-purpose digital computer—1945’s ENIAC—from the smartphone in your pocket, both machines actually work the same fundamental way: by boiling down every task into a simple mathematical system of ones and zeros. For decades, so did every other computing device on the planet.
Then there are quantum computers—the first ground-up reimagining of how computing works since it was invented. Quantum is not about processing ones and zeros faster. Instead, it runs on qubits—more on those later—and embraces advanced physics to take computation places it’s never been before. The results could one day have a profound impact on medicine, energy, finance, and beyond—maybe, perhaps not soon, and only if the sector’s greatest expectations play out.
The field’s origins trace to a 1981 conference near Boston cohosted by MIT and IBM called Physics of Computation. There, legendary physicist Richard Feynman proposed building a computer based on the principles of quantum mechanics, pioneered in the early 20th century by Max Planck, Albert Einstein, and Niels Bohr, among others. By the century’s end—following seminal research at MIT, IBM, and elsewhere, including Caltech and Bell Labs—tech giants and startups alike joined the effort. It remains one of the industry’s longest slogs, and much of the work lies ahead.
Some of quantum’s biggest news has arrived in recent months and involves advances on multiple fronts. In December, after more than a decade of development, Google unveiled Willow, a Post-it-size quantum processor that its lead developer, Hartmut Neven, described as “a major step.” In February, Microsoft debuted the Majorana 1 chip—“a transformative leap,” according to the company (though some quantum experts have questioned its claims). A week later, Amazon introduced a prototype of its own quantum processor, called Ocelot, deeming the experimental chip “a breakthrough.” And in March, after one of D-Wave’s machines performed a simulation of magnetic materials that would have been impossible on a supercomputer, CEO Alan Baratz declared his company had attained the sector’s “holy grail.” No wonder the tech industry—whose interest in quantum computing has waxed and waned over its decades-long gestation—is newly tantalized.
