Microsoft Research Blog

Microsoft Research Blog

The Microsoft Research blog provides in-depth views and perspectives from our researchers, scientists and engineers, plus information about noteworthy events and conferences, scholarships, and fellowships designed for academic and scientific communities.

What problems will we solve with a quantum computer?

July 5, 2017 | By Microsoft blog editor

New paper suggests quantum computers will address problems that could have substantial scientific and economic impact

The MoFe protein, left, and the FeMoco, right, would be able to be analyzed by quantum computing to help reveal the complex chemical system behind nitrogen fixation by the enzyme nitorgense.

With rapid recent advances in quantum technology, we have drawn ever closer to the threshold of quantum devices whose computational powers can exceed those of classical supercomputers.

But when a useful, scalable general-purpose quantum computer arrives, what problems will it solve?

Much work has already been done towards identifying areas where quantum computing provides a clear improvement over traditional classical approaches. Many suspect that quantum computers will one day revolutionize chemistry and materials science; the likely ability of quantum computers to predict specific properties of molecules and materials fits this outcome nicely.

However, a number of important questions remain. Not the least of these is the question of how exactly to use a quantum computer to solve an important problem in chemistry. The inability to point to a clear use case complete with resource and cost estimates is a major drawback. After all, even an exponential speedup may not lead to a useful algorithm if a typical, practical application requires an amount of time and memory that is beyond the reach of even a quantum computer.

Our paper published earlier this week at the Proceedings of the National Academy of Sciences confirms the feasibility of such a practical application, showing that a quantum computer can be employed to reveal reaction mechanisms in complex chemical systems, using the open problem of biological nitrogen fixation in nitrogenase as an example.

Today, we spend approximately 3 percent of the world’s total energy output on making fertilizer. This relies on a process developed in the early 1900s that is extremely energy intensive—the reaction gas required is taken from natural gas, which is in turn required in very large amounts. However, we know that a tiny anaerobic bacteria in the roots of plants performs this same process every day at very low energy cost using a specific molecule—nitrogenase.

This molecule is beyond the abilities of our largest supercomputers to analyze, but would be within the reach of a moderate scale quantum computer. Efficiently capturing carbon (to combat global warming) is in the same class of problem. The search for high-temperature superconductors is another example.

This paper shows that these kinds of necessary computations can be performed in reasonable time on realistic quantum computers—demonstrating that quantum computers will one day tackle important problems in chemistry without requiring exorbitant resources. This paper also gives us further confidence that quantum simulation will be able to provide answers to problems with a tremendous potential for scientific and economic impact.

Editor’s Note: The paper’s authors contributed to this post: Markus Reiher, Nathan Wiebe, Krysta Svore, Dave Wecker and Matthias Troyer.

Related:

Up Next

Image of Dr. Craig Costello for the Microsoft Research Podcast

Algorithms, Quantum computing, Security, privacy, and cryptography

News from the front in the post-quantum crypto wars with Dr. Craig Costello

Episode 94, October 16, 2019 - Dr. Craig Costello is in the business of safeguarding your secrets. And he uses math to do it. A researcher in the Security and Cryptography group at Microsoft Research, Dr. Costello is among a formidable group of code makers (aka cryptographers) who make it their life’s work to protect the internet against adversarial code breakers (aka cryptanalysts), both those that exist today in our classical computing world, and those that will exist in a quantum computing future. On today’s podcast, Dr. Costello gives us a battlefield update in the ongoing crypto wars; talks about different approaches to post quantum cryptography and explains why he believes isogeny-based primitives are among the most promising; and reassures us that, as long as the battle goes on, cryptographers will continue to work very hard on the very hard math they hope will protect us from hackers and attackers, even in the age of quantum computers.

Microsoft blog editor

Quantum computing, Security, privacy, and cryptography

Cryptography for the post-quantum world with Dr. Brian LaMacchia

Episode 38, August 22, 2018 You know those people who work behind the scenes to make sure nothing bad happens to you, and if they’re really good, you never know who they are because nothing bad happens to you? Well, meet one of those people. Dr. Brian LaMacchia is a Distinguished Engineer and he heads […]

Microsoft blog editor