Research conducted by Raissa M. D’Souza, a professor with dual appointments in the UC Davis Departments of Computer Science, and Mechanical and Aerospace Engineering, has been honored with a cover story in the July issue of Nature Physics. The report, “Anomalous Critical and Supercritical Phenomena in Explosive Percolation,” is co-authored by Jan Nagler, of the Department of Computational Physics for Engineering Materials, ETH Zürich, Zürich, Switzerland.
The study focuses on a mathematical concept known as the “percolation transition,” which refers to large-scale connectivity on an underlying network or lattice. Because of the impact on a such a system’s macroscopic behavior, it is desirable to control the location of the percolation transition, in order to either enhance or delay its onset, and, more generally, to better understand the consequences of such control interventions. D’Souza and Nagler have focused on “explosive percolation” — the sudden emergence of large-scale connectivity that results from repeated small interventions designed to delay the percolation transition — which could become an emerging paradigm for modeling real-world systems ranging from social networks to nanotubes.
D’Souza earned her PhD in statistical physics at MIT in 1999, and then completed postdoc work at both Bell Labs and the Microsoft Research Theory Group. She joined the UC Davis College of Engineering as an assistant professor in 2005, rising to full professor in July 2014. She is a member of the UC Davis Complexity Sciences Center, and since 2007 also has served as an external professor at the Santa Fe Institute.
Her research focuses on mathematical models of self-organization, phase transitions and the structure and function of networked systems. Her publications span the fields of statistical physics, applied math and theoretical computer science. In 2012, she and PhD student Charles Brummitt achieved an important “proof of concept” in the relatively innovative fields of network theory and network science. These results were published — in a paper titled “Suppressing Cascades of Load in Interdependent Networks” — in the February 21, 2012, issue of the Proceedings of the National Academy of Sciences.
In July 2013, a team headed by D’Souza received a U.S. Department of Defense Multidisciplinary University Research Initiative (MURI) Award. The $6.25 million, five-year project — titled “Predicting and Controlling Systems of Interdependent Networks: Exploiting Interdependence for Control” — focuses on the control of collective phenomena in complex systems. As project PI, D’Souza is collaborating with colleagues from UC Davis, Caltech, Rice University, the University of Washington, and the University of Wisconsin.
Nature Physics, one of the journals in the Nature Publishing Group, publishes papers in all areas of physics, pure and applied. The journal content reflects core physics disciplines, but also is open to a broad range of topics whose central theme falls within the bounds of physics. Research areas include quantum physics, fluid dynamics, information theory and computation, nanotechnology, high-energy particle physics, astrophysics and cosmology, and numerous other fields.