Just over 40 years after the field of quantum computing began, funding is on the rise locally for the hard-to-explain concept that has huge implications for businesses.

More money is starting to flow into the nascent field of quantum computing in Boston, turning academic research at MIT and Harvard labs into startups.

In September, Northeastern University announced it will build a $10 million lab at its Burlington campus to explore applications for quantum technology, and to train students to work with it. And companies based in other countries are setting up outposts here to hire quantum-savvy techies.

That sounds to me like the beginnings of a cluster, when research, entrepreneurial activity, talent, and funding begin to attract even more of those four elements to a region, in a kind of snowball effect.

“It’s still pretty early” for quantum computing, says Russ Wilcox, a partner at the venture capital firm Pillar. “But a number of companies are starting to experiment to learn how to make use of it. The key factor is that the field is progressing at an exponential rate.”

In 2018, his firm made an early investment in Zapata Computing, a Boston startup building software for quantum computers and selling services — including ways to analyze the new cybersecurity risks that a powerful new class of computers could introduce. (Wilcox explained his thinking about the field of quantum computing that year in a blog post titled “The Time is Now for Quantum.”) Zapata, which spun out of Harvard and is named after a Mexican revolutionary, has raised $64 million. Among its 98 employees and contractors are 36 people who have PhDs.

The field of quantum computing is just over 40 years old; it began to take shape at a 1981 meeting in Dedham, at MIT’s Endicott House conference center, which hosted an academic conclave called the Physics of Computation conference. At the event, the physicist Richard Feynman suggested that when it came to simulating natural systems such as weather, chemistry, and biology, “classical” computing approaches limited to the binary language of ones and zeroes would always fall short. “Nature isn’t classical, dammit, and if you want to make a simulation of nature, you’d better make it quantum mechanical,” Feynman said.

Bharath Kannan, chief executive of the Cambridge startup Atlantic Quantum, picks up the explanation from there. “Mapping the physics of molecules, atoms, and electrons onto conventional computers is very inefficient,” Kannan says. “And when you try to do certain types of simulations, you’re relying on lots of approximations of how they behave, and most of the time they don’t work.”

The question that has been driving the field of quantum computing since the early 1980s is, “What if you had a computer that was natively quantum mechanical,” as Kannan puts it. “It would be game-changing for a lot of industries. Pharma companies could simulate how drug molecules would act inside the body before you waste a lot of money doing clinical trials,” companies could simulate how new types of materials would perform in the real world — whether an airplane wing or a cardiac implant — and weather and climate researchers could more accurately model those systems.

One other force, Kannan explains, was the development of an algorithm in 1994 that, if run on a powerful enough quantum computer, could break any of today’s data encryption. (That scenario has been dubbed the “quantum apocalypse.”) “It got the government scared, and it got the money flowing,” says Kannan. In the current fiscal year, the federal government budgeted about $900 million to advance the field of quantum information science, which includes quantum computing.

Quantum computers store information in qubits, short for “quantum bits.” Unlike the “on” and “off” switches of traditional computers, though, which represent ones and zeroes, and must be in either state, qubits can exist in a “super-position,” being both a one and a zero at the same time. “The English language is not meant to describe quantum mechanics,” says Kannan. “There are really no words that can accurately explain what a qubit is.” (Whew.) But the ultimate goal, going back to Feynman’s vision, is a powerful new class of computers that can solve problems and accurately simulate things that today’s computers can’t. One big challenge will be coming up with efficient approaches to error correction; given a qubit’s ability to exist in a super-position, it is far more likely to introduce errors in calculations than classical binary bits.

Kannan earned his doctorate from MIT this May, and in July, Atlantic Quantum raised $9 million in funding, some of it from Boston-based Glasswing Ventures and The Engine, an investment fund affiliated with MIT. It’s working to design a quantum chip that will run in a super-cold environment — about minus 450 degrees Fahrenheit — but can be manufactured using today’s chipmaking techniques. The company is based at The Engine’s incubator space, just outside of Central Square in Cambridge.

This week, a startup based in Cambridge, England, Riverlane, officially opened an office in Cambridge, Massachusetts. Riverlane, with 80 employees, has six of them based locally, including its chief science officer, Jake Taylor. Taylor spent two-and-a-half years working in the White House’s Office of Science and Technology Policy, providing guidance on quantum-related issues. The company is focused on creating an operating system for large-scale quantum computers that will deal with the error correction issue. Taylor says that Riverlane will be hiring locally, though jobs have not yet been posted, and plans to launch an internship program in January.The company’s Kendall Square outpost, Taylor explains, is primarily for research and development activity.

The quantum workforce — people who can really dig in and make immediate progress — is not evenly distributed,” he says. “A lot of the educational institutions here have been leaders in the foundational science that underpins quantum computing.

In addition to that workforce, several local venture capital firms are getting comfortable with placing bets on the quantum computing sector. Glasswing’s Rudina Seseri says that her firm is “seeing momentum pick up,” although the sector is “still in the warm-up phase, not yet in the first inning.” But some of the technology being developed by startups, she says, “is so meaningful that if they get the technology to work at scale, they will be incredibly valuable.”

That said, much of the revenue available to these companies today comes from researchers in academic and corporate labs trying to understand the potential of quantum computers.

Sam Liss, an executive director in Harvard’s Office of Technology Development, thinks that “the large commercial opportunities for quantum are still a long way off.” The OTD helps attract corporate funding to Harvard research labs, and also helps to license technologies created in those labs to the private sector.

“Technologies have a way of getting oversold and overhyped,” Liss says. “We all recognize that this is going to take some time.”

Large companies like Amazon, Google, and IBM are trying to move the field forward, and startups are beginning to demonstrate their new approaches. In the startup realm, Liss says, we’re seeing enough new companies being formed and attracting funding “to support a thesis that this will be a big thing.”