After some of the basics of quantum computing are explored in the introductory episode of the Entrust Engage podcast, episode two takes listeners deeper into the science behind this topic with an interview featuring Dr. Carmen Palacios-Berraquero, award-winning quantum physicist and CEO of Nu Quantum.  Many interesting areas were covered – from a brief history of quantum computing to what the future benefits of this field might be. Here are the 6 key takeaways from this episode:

#1: The episode kicked off with a concise history of quantum computing, which goes back to the ’80s when people first began to look at how to apply quantum theory to computing. Then in the ’90s, Shor’s algorithm was developed, which significantly sped up the calculation of factorization problems and was the first step in potentially breaking RSA encryption. Experimental physicists also found new hardware in which you could encode quantum information. Progress in quantum computing continued to exponentially accelerate in the 2000s and 2010s and led to a kind of modern-day space race of different hardware approaches. In these earlier years the field was still largely an academic endeavor, whereas in the past seven years the academic pioneers of this race moved into the industry to set up startups. In 2019, Google declared “quantum supremacy.” And in 2021, more than $3 billion was invested into quantum computing, further cementing its importance to the future of technology.

#2: So, what exactly is “quantum supremacy”? For starters, Dr. Palacios-Berraquero prefers the term “quantum advantage.” When Google announced that it had achieved this, what did that really mean? How significant was this?

Well, Google was essentially successful in using quantum computing to solve a problem that would have been infeasible for a classical computer. However, the problem it solved had no application in the real world. While the industry is moving toward solving commercially useful problems, there is still progress to be made before any organization can consider itself to have a true quantum advantage.

#3: There is consensus that the quantum computing threat to traditional public key algorithms will be a reality within the decade. However, taking Google’s 2019 claim of quantum supremacy into consideration, the question arises: Has this timeline been accelerated?

The answer: not necessarily. There are two main factors to consider here. The first is that it is very hard to scale these machines. The second is that there are lots of errors in quantum computers’ processors. Error correction schemes are very complex and take up quite a few logical qubits in quantum computers, leaving fewer qubits to perform logical computations. So, even with the progress made at present, the threat timeline of quantum computers has not accelerated.

#4: Is the news about quantum computing all about its threats and challenges? Echoing what we learned from episode one, absolutely not! There are major benefits that quantum computing can unlock in the future. For starters, quantum computing can crack those intractable problems we can’t currently solve today. This opens entirely new applications, markets, and industries. Some examples include both material and drug design, paving the way for innovations in healthcare and the battle against climate change. In the near term, quantum computing promises benefits like financial portfolio optimization, improvements in machine learning algorithms, and the simulation of quantum and physical systems.

#5:  What is a quantum random number generator and how different is it from what we know of entropy in cryptography today? The quantum random number generator is based on the main proposition of quantum theory that the outcome of a measurement is completely unpredictable. It uses this principle to generate entropy/random numbers. Over the past decade, it has been proposed to use these generators as a source for cryptography.

The main difference is that entropy used in cryptography currently is based on classical mechanics, where theoretically everything is predictable. In theory, by knowing the exact functioning of a system and combining it with a lot of computing power, you could predict the outcome of a classical random number generator.

The reality is quite different, though. Current cryptography uses mathematical tools in addition to a random number generator, making it quite impossible to crack. While the industry is debating the use and applications of a quantum random number generator, it’s still a long way from adopting it in cryptography.

#6: Additional benefits in development include quantum computing as a service (QCaas) and quantum internet. These are two very different things. QCaaS is a means by which users can access quantum computers via the cloud. For example, AWS hosts around five quantum computers, and a user can buy time on them through the cloud and run various algorithms. And there’s a long line of users queued up to use these computers. Who are these users? A mix of academics and researchers as well as R&D departments in industry. However, these machines are still in the labs of companies, and it will be a while before they can function independently in a data center.

Now let’s unravel the service known as quantum internet. Picture a computer network that can send quantum information between distant computers, and there you have it in a nutshell. This technology is still largely contained to the realm of academia, and it’s still unknown what the exact commercial application will be. What we do know is that it’s still some years away.

The science behind quantum computers is pretty fascinating, and if you’re looking to learn more, I recommend listening to the second episode of Entrust Engage. For more information and resources on post-quantum and how to prepare, visit our webpage.