Prof. Rob Phillips (Caltech) took the audience through a fascinating journey of viral dynamics in the webinar, ‘Where is Euler Now That We Need Him?’. Prof. Phillips used questions which have arisen in biology and physics to illuminate the current systems of understanding the SARS-CoV-2 (COVID-19) pandemic. He dedicated the talk to an analogy between the history of celestial mechanics and the history of “viral mechanics”, harkening back to the 1750s when Euler, d’Alembert and Clairaut were engaged in a careful study of the lunar orbit.
This session provided a remarkable perspective of viruses and the need for patient, rigorous analysis to understand the various facets of this virus, which we will continue to face for an uncertain period of time. Using the many examples from history where scientists spent decades on a single question, Prof. Phillips made a strong case for what he terms the “biological numeracy” approach, which has inspired many scientists over the years. The use of numbers and quantitative thinking in biology will transform it, and help tackle the age of pandemics we appear to be in. To understand this virus (and others) which are clearly evolving, numbers provide a pathway, especially in a time of uncertainty and rapid developments. Prof. Phillips illustrates some of the questions where thinking by numbers has been helpful, such as scaling--e.g. the thickness of an animal leg to support its body weight-- which was raised by Galileo, back in the 1600s.
A minimum infectious dose (such as the minimum number of photons needed to see), was one avenue of discussion. The mechanics viruses use to infect cells, fitting the pandemic spread in different countries, the steps toward understanding the COVID19 virus transmission, and numerous other ideas at the biology-physics interface were highlighted in this talk, moderated by Dr. Mukund Thattai and Prof. Satyajit Mayor of NCBS. This is the first in a series of webinars, ' Web Gyan', by scientists on topics related to the COVID-19 pandemic, under the COVIDGyan initiative, a collaboration between the TIFR institutes and partners such as IISc, IndiaBioScience, Tata Memorial Centre, inStem, and Vigyan Prasar.