Perhaps no one fully understands quantum computing yet, but one thing is clear: expectations are high. And where there are high expectations, there is money.

Both private and public funding for European quantum technologies has grown significantly in recent years. Private funding for quantum startups in 2021 increased by 2.5x compared to 2020, and by 8x compared to 2019. Public funding has also increased, with the EU planning to invest $7.2 billion (€6.8 billion) in quantum computing projects by 2025.

Understandably, most of these billions have already been or will be spent building a successful quantum computer – hardware is currently the biggest bottleneck in deploying this technology. However, let’s not forget that hardware alone is not enough. Quantum computers have no value without suitable software.

Yet quantum software gets undeservedly little attention and thus funding.

A quantum “chicken or the egg” challenge

An obvious example that quantum software is undervalued in Europe is the distribution of money in the EU Flagship quantum technology program — the ambitious initiative to support Europe’s quantum innovations with a total of €1 billion in funding. The first phase of this initiative has concluded with €152 million invested. Of that, only €4.6 million – that’s only 2.9% – went to research and development of quantum software.

When it comes to private investment, the situation is better, albeit similar. In 2021/2022 approximately 14.5% of equity investments in European quantum computing startups went to software solutions. And it looks like this trend will continue into 2023. Europe’s quantum computing startups that delivered notable rounds this year – inclusive Pascal (€100 million), Quantum movement (£42 million), Oxford lonics (£30m) – are all hardware-focused.

In the tech world, such a focus on the hardware is unusual – in every other field, software typically receives the bulk of investment due to easier scalability and greater profit opportunities. So why, when it comes to quantum technology, is it the other way around?

The reason for this anomaly is this: Both private investors and public funds view quantum computing as a hardware problem rather than a software problem. And to some extent they are right: building successful quantum hardware is indeed the biggest challenge. Well, now. But in the grand scheme of things, it’s only a third of the problem.

The three hurdles to jump

When it comes to quantum computing, there are three central problems we have yet to solve.

The first and most obvious is building a quantum computer. There are currently no quantum computers used for more than experimentation, so this is where the industry is primarily focused – from the world’s tech giants, such as Google and IBM, to startups and academia.

The second challenge is to reduce errors in quantum computers so that they can perform longer computations. Better hardware reduces the number of errors, but is probably not enough on its own. We need to find ways to correct quantum computer errors at the software level.

And the third problem is finding more computing methods for quantum computers, that is, quantum software applications. Quantum computers will be useful for modeling physics and chemistry, but the extent of their usefulness for data processing – from machine learning to planning and scheduling – is less clear. If we could find a few more methods to expand the scope of the problems these computers can solve, it would be fundamental progress.

Therefore, two of the three central quantum computing problems are software related. But why is it that this is not reflected at all in the distribution of resources? Given that we’re already putting (okay, most of) the available money into hardware, how does anyone expect to be able to run this new supercomputer without the “brain” that actually powers it?

It may not be a software issue today, but it will be tomorrow

A reasonable split of funding, in my opinion, would be 15-20% for quantum software and 80-85% for hardware.

Simply put, hardware is the most expensive and complex part of this technology, so it is rational to allocate the largest amount of money to it to speed up development. And sending one-fifth of the total funding to software would be enough to cover R&D work on new quantum computing applications.

While the distribution of private investment may not seem so hopeless, the EU’s public resources are light years away from achieving this goal.

Look, the development of quantum software takes years. It took my colleagues and me between five and ten years to develop quantum walks as a problem solving method. I expect a similar timeline for new problem-solving methods of comparable or greater significance.

What worries me is that if we continue to ignore quantum software, quantum computing will become a software problem in about 10 years – and a life-or-death problem. Quantum computers will be developed, mainly with applications in physics and chemistry. In other areas, they will still be used primarily for experimentation rather than actual problem solving.

In other words, Europe is now spending billions on specialized computing equipment that it may not be able to adapt to wider applications. And if we cannot provide software that would expand the application of these devices, we risk losing interest in this technology and its further development. The range of applications will simply be too small for the world to care.