The calculations that arise in theoretical high-energy physics are very complicated and typically analytically intractable using “pen & paper” approaches. As a result, numerical methods and large scale computer simulations have long been employed in this field in order to obtain quantitative results that are not accessible by analytical means. While some significant successes have been obtained over the past thirty years or so, and thanks to the usage of massive simulations carried on supercomputers, many fundamentally important questions remain open because conventional (i.e. classical) computers are far from being sufficiently powerful. Quantum simulators capitalize on the exotic properties of physical quantum systems for realizing computations that cannot be performed with conventional computers. The field holds the potential to answer questions that have eluded particle theorists for decades such as: What is the nature of the nuclear matter inside a neutron star? What exactly happened during the Big Bang? Why is there more matter than anti-matter in nature and hence why do we exist?
“Such questions belong to a subclass of very hard problems that cannot be solved with super computers – and this is where quantum computing shows incredible promise.”
The idea of using quantum simulators to study high energy physics is rather recent. “We are busy developing a new type of quantum simulator and not focusing yet on answering the grand questions.” said Christine, “and, right now, the field is just taking its first baby steps”. In this context, Muschik and a team of researchers at the University of Innsbruck, including Peter Zoller and Rainer Blatt, successfully created in 2016 the first quantum simulation of a simple one- dimensional version of quantum electrodynamics – a quantum theory of electromagnetism. Acknowledged as a top 10 breakthrough of the year by Physics World, that work proved that it is possible to use quantum simulation techniques to study fundamental forces of nature and, from there, particle physics.
Christine’s interest in theoretical physics goes back to when she was 15 and joined her high school’s science club. She earned a BSc in physics at the Ludwig-Maximillians-Universität (LMU) and then pursued her PhD at LMU and the Max Planck Institute of Quantum Optics under the supervision of J. Ignacio Cirac. Her theoretical research in quantum optics earned her the Alexander von Humboldt postdoctoral fellowship, which she took to work with Maciej Lewenstein at the Institute of Photonic Sciences (ICFO) in Castelldefels, Barcelona. She then continued her postdoctoral research with Peter Zoller at the Institute for Quantum Optics and Quantum Information (IQOQI) in Innsbruck, Austria, and was a university assistant at the University of Innsbruck’s Institute of Theoretical Physics before coming to Waterloo. While having been in Waterloo for a mere two years, she has already been recognized by a number of important awards for her research. In 2018, Christine was named as an Emmy Noether Visiting Fellow at the Perimeter Institute for Theoretical Physics. The fellowship supports early- and mid-career women physicists, and honours the legacy of scientist Emmy Noether who was described by Albert Einstein as “the most important woman in the history of mathematics.” In 2019, she received a prestigious A.P. Sloan Fellowship. Also in 2019, Muschik and her colleagues from the Physics and Astronomy Department, Rajibul Islam and Roger Melko, received a New Frontiers in Research Fund (NFRF) grant for a joint project that aims to build the first quantum simulation with ions in Canada. Awarded in the NFRF’s exploration stream, their project Quantum simulations of fundamental interactions with artificial intelligence, is recognized as an avenue to “generate opportunities for Canada to build strength in high-risk, high-reward and interdisciplinary research.” The new project brings together a diverse team of expertise in high-energy physics, quantum technologies, chemistry and computer science.
Right now, Muschik and her group at the University of Waterloo are busy on building more complex simulations, with an eye on quantum chromodynamics (QCD) which describes the interactions between quarks – the fundamental elementary particles that constitute the interior of atomic nuclei. Interestingly, while this type of research is very fundamental in its nature, the industry is paying attention to this forefront research with companies such as Google, IBM and Rigetti Computing showing interest.
“The best way to describe the field is a bridging of perspectives”
said Muschik. “You’ve got theory and experiment, quantum and high-energy physics, and industry and academia all coming together. It’s really quite exciting. This line of research has the potential to dramatically advance our understanding of some of the most challenging questions in modern physics. Further down the road, the quantum simulation tools developed in this context will be widely applicable and could even revolutionize simulations in such diverse fields as chemistry, biology, material science and medicine.” Christine Muschik’s research program epitomizes a rapidly growing trend in theoretical physics worldwide, and one that the Physics and Astronomy Department is actively engaged in: the merging of different subfields of theoretical physics, that combines numerous analytical and numerical approaches and that is simultaneously interlaced with ambitious experimental pursuits. Proceeding that way, it is broadly felt that breakthrough discoveries will be made and, thanks to the hiring of young creative researchers such as Christine Muschik, the Department of Physics and Astronomy at the University of Waterloo is poised to make a mark on the international scene.
