# Ask an MIT Professor: Dr. Will Oliver Discusses the Past, Present, and Future of Quantum Computing

Think quantum computing is only relevant to professionals in the fields of computer science and physics?

Think again.

The quantum computing revolution is here, and professionals and leaders in business, government, and technology can benefit significantly from understanding quantum computing’s business and technical implications.

With an estimated 20% of organizations budgeting for quantum computing projects by 2023, now is the time to learn quantum computing online and become the expert your organization needs.

We recently caught up with MIT Professor Will Oliver, faculty director of MIT xPRO’s Quantum Computing Fundamentals course, to hear his take on the past, present, and future of quantum computing—and why professionals across industries should care about it.

**A Brief History: Quantum Computing Becomes a Hot Topic in STEM**

Quantum computing, which leverages the principles of quantum mechanics to solve complex problems that classical computers can’t, began in the summer of 1981 at a famed gathering hosted at MIT’s Endicott House.

MIT quantum physicist and Nobel Prize in Physics recipient Richard Feynman proposed that simulating a quantum system should involve using another quantum system, noting the difficulty of fully simulating a quantum system on conventional computers. “It was an interesting idea,” says Professor Oliver, “but the question was. . . how do you do it?”

The answer didn’t come for another 10-15 years. By the 1990s, the first quantum algorithms were published. One notable algorithm that emerged was Shor’s algorithm, named after MIT quantum computing expert Peter Shor (who also happens to be an instructor in Professor Oliver’s online Quantum Computing program), which, Professor Oliver explains, “attacks public-key crypto, one of the foundations of our current online information security.” Shor and his colleagues also developed quantum error-correcting schemes to correct errors that occur on quantum computers.

The 1990s brought significant developments in trapped ion quantum computing as well, through efforts helmed by David Wineland and colleagues. “They began showing that trapped ions were candidates for the qubits that would become a quantum computer,” explains Professor Oliver, “and the first superconducting qubit was demonstrated in 1999.”

In the early 2000s, MIT’s Isaac Chuang, another instructor in MIT xPRO’s online Quantum Computing program, demonstrated that it’s possible to factor 15 into 3 x 5 using Shor’s algorithm. “Of course, we can all do that in our heads,” admits Professor Oliver, “but it was a very important demonstration, because it showed that Shor’s algorithm works.”

From that point forward, the conversation shifted toward determining how to build the systems to run quantum algorithms at scale so that they could become commercially meaningful.

**Major Developments in Quantum Computing from 2000-Present **

“There has been a remarkable improvement in the quality of qubits in the period from 2000 to today across all modalities,” says Professor Oliver. For example, superconducting qubits evolved from nanosecond coherence times in 1999 to well over 100 microseconds today due to a combination of materials, fabrication, and design improvements. Professor Oliver believes these advances represent a huge leap forward in just two decades.

“Trapped ion computers and superconductors are at the forefront today,” he says, adding that there have also been significant advances in photonic quantum computing, neutral atoms, and semiconductor quantum computing.

He compares Google’s 2019 demonstration of quantum supremacy to the Wright brothers making history at Kitty Hawk. Both were barebones demonstrations meant to prove that something revelatory was possible.

“Google showed that they could run their algorithm in 200 seconds with only 53 qubits and 100 kW of power,” explains Professor Oliver. “To simulate exactly what that quantum computer did would require the number-one supercomputer in the world at the time, and even then, it would have taken all of its 10E17 transistors a couple of days and hundreds of megawatts of power.”

The demonstration highlighted the vast disparity in resources needed to accomplish the same task on quantum machines versus traditional ones, revealing the advantage that quantum computing can afford.

**Modern Industries Benefiting from Advancements in Quantum Computing **

Thanks to ongoing efforts to make quantum computing more commercially relevant, applications for quantum computing are foreseeable when quantum hardware reaches a larger scale.

**How Quantum simulation may help the pharmaceutical industry in the future**

Simulating quantum systems is useful in various fields, from pharmaceutical and drug development to materials sciences to chemistry.

Take, for instance, a pharmaceutical company developing new drugs to treat cancer. “These companies spend significant money on drug trials that end up going nowhere, but they can’t make that determination until they’re far into the process,” explains Professor Oliver. “If they could simulate what’s going to happen in advance, it would make a big difference.”

Another example is developing better materials, such as materials for longer-lived batteries.

**How optimization and solutions to linear systems of equations could impact manufacturing supply chains and aeronautics**

The need for optimization spans every aspect of our lives, commercially and personally. “Everybody has to optimize something,” says Professor Oliver, ”whether it’s a financial portfolio, a manufacturing supply chain, or a trip home from work.”

Quantum optimization may prove to be useful, though Professor Oliver acknowledges that the actual advantages are still unknown today.

Quantum computers have the potential to sample solutions to differential linear equations that could address fluid flow problems and other similar issues in aeronautics, for instance.

**How quantum computing could disrupt public-key cryptography **

One area that is especially ripe for quantum computing disruption is public-key cryptography. “Building upon Shor’s algorithm, which breaks the public-key cryptography in common use today, we need to transition to post-quantum cryptosystems that we believe are immune to attack by quantum computers,” says Professor Oliver.

He explains that the cryptosystems currently being used to exchange keys on the internet are susceptible to an attack by a future quantum computer. “That computer hasn’t been built yet, but we know it’s coming in the next 10-20 years,” he cautions.

**What’s Next for Quantum Computing?**

“We are currently in what’s called the ‘noisy intermediate-scale quantum’ (NISQ) era, in which we have small quantum processors (approximately 50-100 qubits) that are error-prone and will fall apart after about 100 operations,” explains Professor Oliver.

The next step, he says, is determining if a hybrid algorithm could enable a classical and quantum computer to work in tandem. The classical computer would run most of the algorithm, polling the quantum computer at certain points for quick answers.

Long-term, however, there is a need for error-protected, fault-tolerant quantum computers capable of conducting large-scale simulations or optimizations to solve commercially relevant problems. “Large efforts are going into quantum error correction, which is a means to essentially achieve robustness in the computer at the expense of added resources,” says Professor Oliver. “Adding more qubits improves the overall system performance, provided the individual qubits are good-enough.”

Error-protected, fault-tolerant quantum computers are needed for general, universal quantum computation. “We cover that in the Quantum Computing Realities program,” notes Professor Oliver, which is recommended for learners who have completed the Quantum Computing Fundamentals course.

**Quantum Computing Isn’t Only for Computer Scientists **

When people ask Professor Oliver why professionals in fields outside of computer science and physics should care about quantum computing, he likens it to learning classical computing.

“Why should people who don’t build classical computers or work with semiconductors care about them? Well, it’s because of all the applications they will enable! The same logic applies to quantum computing,” he says.

He then makes the critical point that most people who end up interfacing with a quantum computer will do so through a terminal. As a result, many professionals who choose to learn quantum computing online are *users* of quantum computers—not *makers*.

They take the Quantum Computing Fundamentals course that Professor Oliver teaches to help them find answers to questions like:

- What is quantum computing?
- How could quantum computing affect my company’s bottom line?
- What quantum computing advancements are currently in development, and how can I filter out the hype?
- How can I become a trusted expert on quantum computing within my organization?

**Advice to companies and professionals **

If anything, Professor Oliver wants people to realize that quantum computing is real, it’s happening around us right now, and it *will* have a major effect on companies’ bottom lines in the future.

His advice to organizations is to have a small internal team begin looking into quantum computing to determine its impact. “There’s a great course for that!” Professor Oliver laughs. “Don’t bet the farm yet, but don’t ignore what’s coming. There’s no better time to start than right now—and no better place to begin your journey than MIT.”

*To learn more about the online quantum computing courses in Professor Oliver’s MIT xPRO program, **check out the program page**!*