Alexander Petroff, Ph.D.Raymond and Beverly Sackler Fellow
Center for Studies in Physics and Biology
Dr. Petroff studies mathematical forms in nature. He has previously investigated pattern formation in stream networks and microbial communities. His current work seeks to understand how the sulfur-oxidizing bacteria in the genus Thiovulum organize into centimeter-scale communities. Within these communities, each bacterium tethers itself to the community and beats its flagella, generating macroscopic flows that pull nutrient-rich water through the community. In doing so, the community generates collective modes that mix the environment over length scales many times larger than the size of a cell. Dr. Petroff uses a combination of theory, experiments and field work to understand how the macroscopic transport of nutrients through the community arises from the microscopic behavior of individual cells.