MPIDS Colloquium: Soft matter physics and the COVID-19 pandemic

Much of the science underpinning the global response to the COVID-19 pandemic lies in the soft matter domain. Coronaviruses are composite particles with a core of nucleic acids complexed to pro-teins surrounded by a protein-studded lipid bilayer shell. A dominant route for transmission is via air-borne aerosols and droplets. Viral interaction with polymeric body fluids, particularly mucus, and cell membranes controls their infectivity, while their interaction with skin and artificial surfaces un-derpins cleaning and disinfection and the efficacy of masks and other personal protective equip-ment. The global response to COVID-19 has highlighted gaps in the soft matter knowledge base. I will survey these gaps, especially as pertaining to the transmission of the disease, and suggest ques-tions that can (and need to) be tackled, both in response to COVID-19 and to better prepare for fu-ture viral pandemics.