This is the most interesting area from a developer perspective and could affect our software and way of working the most. To understand what could be the impact of Quantum Computing we first need to identify what kind of problems Quantum computing solves that classical computers can’t.

To understand what problems can be solved we first need to look at “Problem classification”. This is a subject on it’s own and can spread multiple blogs to explain, so I will reference the excellent article on this topic by Sara A. Metwali Complexity theory 101.

Problems that require resources that scale exponentially with the size of the problem are hard or nearly impossible to solve with classical computers. This is the area where Quantum computers will provide the greatest benefit. So what kind of real life problems could we be talking about here.

In order to prepare our applications for the use of Quantum Technology the architecture of your application is very important. You want to be able to run parts of your application on classical computers and some or maybe just one part or service on a Quantum computer. Although it may take many years before quantum computers are widely available, simulators can be used now to work on Quantum software. As Software Engineers we know it also takes time to change systems and have them using different technologies. So starting early makes the transition more seamless.

My colleague Jasper Bogers wrote an excellent article (in Dutch) about the use of Hexagonal Architecture. This architectural pattern promotes the Separation of Concerns by encapsulating logic in different components of the application. This enables a higher level of isolation, testability and control over your business specific code. Each component of the application has a strict set of responsibilities and requirements. This creates clear boundaries as to where certain logic or functionality should be implemented, and how those components should interact with each other. The picture below shows such an architecture and how this utilizes both Quantum and classical compute power.

So in the case of a ‘Hybrid’ application with components that require to be executed on a classical computer and components that benefit from Quantum compute power, this architecture provides you the means to do so. There are many use cases out there but, like I discussed before, the logistic problems are for some reason more appealing to me. What if we could utilize the optimization algorithms and assign routes more efficiently. This could have a massive impact on the travel and logistic companies out there. A recent study at Chalmers University of Technology in Sweden proves this on a small Quantum computer.

Looking at Quantum Technology and Software Engineering, we are at the dawn of a new era where the revolution is mainly focussed on the hardware side of the picture. However, without real world problems to solve - and good software to solve it with - the puzzle is only partially complete.

All of my latest blogs featured quotes of one of my childhood heroes, Michael Jordan. Scrolling through his wisdom quotes I found this one highly suitable for where we currently stand and how I feel about Quantum Technology.

I hope that we as Software Engineers will get more involved in this revolution and help to find the right pieces to the puzzle. We can shape the future by making programming for Quantum Software less complex without losing its power.

Erik