Fall 2020 > IAS Scholars

The Flow of Life

Prof. Jason Tin-Lun HO, a theoretical physicist in condensed matter physics, has been associated with the IAS since 2011. As one of our IAS Senior Visiting Fellows, Ho comes to HKUST from time to time to share his latest research findings with faculty members and students by giving distinguished lectures and carrying out collaborative research projects. Often flashing his warm signature smile, Ho can easily strike up a friendly conversation with those around him. We took the opportunity to sit down with Ho during his recent visit to the IAS, to discuss his enthusiasm for research and outlook on life.

“I came from a humble background, and studying in the university had always been my dream.” Ho, modest as usual, added, “At that time, earning a degree could land you a better job and possibly help you claw your way to the top.”

Thanks to his interest in mathematics and physics, at which he excelled academically in secondary school, Ho was eventually accepted by the Chinese University of Hong Kong (CUHK) to study physics. “These two subjects were like a game to me — based on a few rules to deduce a great variety of outcomes! I chose physics as a major because it describes phenomena that a person can directly observe.”

Ho expressed that he felt blessed to have brainy friends to hang out with at the university. “They introduced to me The Feynman Lectures on Physics by Prof. Richard FEYNMAN, which was beautifully written. It inspired me to carry out research in physics as a profession,” Ho recalled. Feynman’s widely read book is a manuscript of lectures that he gave at the California Institute of Technology. No physics student, teacher or scientist would be unfamiliar with Feynman, who shared the 1965 Nobel Prize in Physics with Japanese physicist Prof. Sin-Itiro TOMONAGA and American theoretical physicist Prof. Julian SCHWINGER for “their fundamental work in quantum electrodynamics, with deep-ploughing consequences for the physics of elementary particles.”1

After graduating from CUHK Chung Chi College in 1972, Ho could have stayed in Hong Kong and become a teacher, but he chose to continue his graduate education in the United States. “I love doing research, but there was no such opportunity in Hong Kong,” said Ho. When he arrived in Minnesota and began his first year of graduate school, things were not what he had imagined.

“I didn’t have friends!” said Ho with a hint of sadness creeping into his smile. Obviously, no one would expect a friendly and gregarious person like Ho to have encountered such a situation. After a year of struggling with social isolation, Ho pondered leaving, even though he attained excellent grades. His professor, who saw his potential, recommended Ho to another professor at Cornell University. Four months later, Ho was at Cornell, which proved a welcome breath of fresh air to him.

The Watershed Moment

“Cornell was a place where I grew up professionally. Many outstanding students from all over the world came to Cornell during this exciting time of great discovery, when many experiments were carried out and research flourished,” said Ho, who remains very enthused about what happened more than 40 years ago. And he was right. A few years before his arrival, the superfluidity in helium-3 was discovered in the low-temperature laboratory at Cornell by Professors David M. LEE, Douglas D. OSHEROFF, and Robert C. RICHARDSON. Their work in low-temperature physics gained them a Nobel Prize. In 1982, another professor at Cornell, Prof. Kenneth G. WILSON, received the Nobel Prize in Physics for “his theory for critical phenomena in connection with phase transitions.” Indeed, to many young PhD students like Ho, the 70’s and 80’s were the golden age to test, trial and to make new discoveries in fundamental physics.

“The training at Cornell made me a better researcher,” said Ho. For him, the choice of becoming a theoretical physicist was obvious. “I like theories relevant to mathematics. It is the understanding of how nature works that really interested me. I don’t have any talent in experiments, and sitting in the lab would be too boring for me!” Deeply intrigued by physics, Ho was also greatly inspired by his thesis advisor, Prof. David MERMIN, Horace White Professor of Physics Emeritus at Cornell, a solid-state physicist best known for the eponymous Mermin–Wagner theorem.

“Mermin is such an original and deep thinker who has a unique way of teaching — he shows you what he did, which was incredibly original, and sees if you can make further progress by thinking outside the box. If not for him, I would not have ended up in physics. He was very patient with me,” said Ho graciously, also recalling that Mermin is famous for his writing.

To many science students, mastering the skill of academic writing is already daunting, even before the challenge of putting complicated scientific concepts into words. That is why Ho admired Mermin for being a prominent solid-state physicist and at the same time a highly articulate science writer who has published seven books and voluminous academic papers. As American physicist Peter FRANKEN said in Physics Today, “David Mermin is one of those rather rare scientists who can write with cleverness and style.”2

A Soul-Stirring Mission

Ho, who has taught at Ohio State University (OSU) for 37 years, is now a Distinguished Professor of Mathematical and Physical Sciences in the Department of Physics there. The pinnacle of his research career occurred when he was awarded the Lars Onsager Prize of American Physical Society in 2008 for “his contributions to quantum liquids and dilute quantum gases, both multi-component and rapidly rotating, and for his leadership in unifying condensed matter and atomic physics research in this area.”3 Even now, the two things that lie firmly at the heart of this theoretical physicist remain research and teaching.

“I love the beach. Doing research is like strolling along the beach. Every now and then you, as a researcher, seem to find something. Whenever I have new discoveries or see a different aspect of things that I have proposed, I am thrilled. It is hard to explain the emotion, but many scientists would agree with me that the journey of discovery is more memorable than the results themselves,” said Ho.

Ho, as an internationally recognized scholar whose work focuses on condensed matter theory and ultra-cold quantum gases, has always been interested in the so-called macroscopic quantum phenomena, in the relation between geometry and physics.

“Simply put, I study materials in which the mysterious quantum processes of the atomic world are magnified to a macroscopic level. As many quantum processes do not generate heat, their magnification can lead to great savings in energy and useful applications,” Ho added, “and there are in fact many practical applications of physics. That’s why I want to understand the laws of nature. There are also many questions within our field that I want to answer, such as how to realize a room-temperature superconductor, how to control individual quasi-particles [localized excitations] in quantum Hall systems efficiently so they can be used to build quantum gates [the hardware of a quantum computer], how to simulate dynamic gauge fields, the simulating processes in high energy physics with cold atoms…the list can go on.”

Ho, obviously infatuated with research more than ever, hopes that his efforts can help eventually advance a few frontiers. Currently, he is trying to finish a paper on recent topics related to quantum simulation of the Hubbard model, non-abelian exchange of particles, and quantum gases in inflating manifolds.

Always sparking with passion for science and life, Ho said, “Science is a discipline in which people can use their rational thinking — the best gift from God — to understand the work of the physical world. The process of understanding the concepts of physics and science allows us to advance the quality of our material and spiritual life.”

In addition to research, Ho also wants to pass his overflowing passion for physics on to the next generation. He picked up the task of teaching undergraduate students again in 2018 and enjoyed it tremendously.

“I last taught undergraduate courses 10 years ago. In the past, I mainly taught postgraduate students because their course work is research-oriented. To me, it was like training up a group of specialized technicians.” When Ho was a Member of the Academic Committee of Institute for Advanced Study at Tsinghua University, China, he organized activities and gave many talks related to his field. “I am glad to see that some of the outstanding students whom I met there have come to OSU. Teaching undergraduate students is different, and all I hope is that they can be inspired,” said Ho earnestly. As he said when he received the OSU Distinguished Scholar Award for his exceptional scholarly accomplishments in 2002, “the simplest way to get rid of fear [about physics] is to get curious about what’s going on in nature.”4

Before the interview ended, Ho spoke fondly of his family, wife and two daughters. “I think I am an incredibly lucky person. I don’t take this lightly.” Perhaps it is Ho’s innate modesty that makes him such a keen scientist and devoted teacher whose sense of true happiness always speaks for itself.

Prof. Jason HO Tin-Lun

Prof. Ho graduated from Chung Chi College of the Chinese University of Hong Kong in 1972 and received his PhD at Cornell University in 1977 under the supervision of Prof. David Mermin. He joined the faculty of the Ohio State University in 1983 and is currently a Distinguished Professor of Mathematical and Physical Sciences in the Department of Physics since 2002.

His research covers the field of quantum fluids, quasi-crystals, quantum Hall effects, and quantum gases. He has studied the topological properties of superfluid He-3 and has done pioneering works in different areas of quantum gases. Ho has served on many advisory and review committees of the funding agencies of the United States, Canada, Australia and China. He was also a board member of Aspen Center for Physics for ten years.

He is recipient of the Lars Onsager Prize of American Physical Society for his contributions and leadership in cold atom physics in 2008. He has been a Guggenheim Fellow, a Simons Fellow in Theoretical Physics and a Sloan Fellow. He has also been elected a Fellow of the American Physical Society, the American Association for the Advancement of Science and the American Academy of Arts and Sciences.