Yang-Yu Liu

Yang-Yu Liu

Visiting Research Assistant Professor


I am a statistical physicist by training, with expertise in analytical calculation, modeling and data analysis. My Ph.D. research encompassed a broad range of topics from statistical to condensed matter and biological physics. Currently, I am working on complex networks and systems biology. The primary goal of my current research is to combine tools from control theory, network science and statistical physics to address the challenging questions pertaining to controlling and observing complex biological systems, which could have a major impact in network medicine, a rapidly developing field that applies systems biology and network science methods to human disease. I received my Ph.D. in Physics from the University of Illinois at Urbana-Champaign in May 2009. My Ph.D. thesis focused on the study of an unexpected universal behavior in disordered magnetic systems. This work has been featured in Europhysics News and selected for the Europe Physics Letter — Best of 2009 Collection. In addition to the theoretical study of statistical physics, I have collaborated with condensed matter experimentalists on the modeling of perpendicular recording media, which is the state-of-the-art magnetic storage application. I have also been collaborated with experimental biophysicists on developing an efficient algorithm for time-binned data analysis in single-molecule experiments of living cells. I served as a Postdoctoral Research Associate in the Center for Complex Network Research (CCNR) at Northeastern University (NEU) from June 2009 to September 2012. From October 2012 to July 2013, I was employed as a Research Assistant Professor in CCNR. I was responsible for writing research papers, presentations and grant proposals. My research has focused on the quantitative study of the dynamic properties of complex systems. In particular, I found that by exploring the underlying network structure of complex systems, one can determine the driver (or sensor) nodes that with time-dependent inputs (or measurements) will enable us to fully control (or observe) the whole system. These findings significantly further our understanding of the intricate interplay between the structural and dynamical properties of complex systems. My work has been featured as a cover story in Nature (May 12, 2011) and a cover story in the Proceedings of the National Academy of Sciences of the U.S.A (Feb. 12, 2013), and received broad media coverage including Nature News & Views, Science News & Analysis, ScienceNews, ScienceDaily, Wired, PHYSORG, and Faculty of 1000. Currently, I am working at the Channing Division of Network Medicine at Brigham and Women's Hospital as an Associate Scientist; and Harvard Medical School as an Assistant Professor. I have been heavily working on the stability and control issues of complex networked systems, especially ecosystems. I believe that dynamic modeling and stability analysis will deepen our understanding on the complexity of ecosystems, e.g. the human gut microbiome. In summary, my primary academic focus has been interdisciplinary research on controlling and observing complex biological systems. In addition to research, I am interested in teaching and professional service. I have been on the Program Committees of five international meetings, on the Editorial Board of two international journals, and an ad hoc reviewer for 42 international journals (including Nature, Science, Nature Physics, Nature Communications, Physics Review Letters, IEEE Transactions on Automatic Control, etc).