Title: Lessons from the study of acoustic waves
Speaker: Dr Jesse Coburn (Imperial)
Abstract: In gaseous systems, waves that perturb the particle density are called acoustic. By the equation of state, these perturbations cascade to higher-order moments. A firm understanding of how the chain-of-moments is perturbed is inherent to the thermodynamics, statistical mechanisms, and fluid-closure of the physical system. This property has guided our physical intuition since the beginning of modern science. I will begin by revisiting how Isaac Newton first grappled with predicting the speed of sound, and how Simone Laplace resolved it through the emerging field of thermodynamics. From this historical foundation, I will move to the case of weakly collisional plasma and discuss the acoustic wave in a general context. Finally, I will close with my current work on how the properties of acoustic waves continue to unveil the beauty of gaseous systems.