Explore a comprehensive lecture on physics across various length scales, delivered by R Shankar at the International Centre for Theoretical Sciences. Delve into the evolution of string theory from its 1970s origins to its current applications in quantum gravity, black hole physics, hydrodynamics, condensed matter systems, and particle physics. Examine topics such as the Nambu Jona-Lasinio Model, Planck scales, quantum matter, Bose-Fermi interactions in 2D, exclusion statistics, and the Hofstadter butterfly. Investigate real-world phenomena including the 2004 Bay of Bengal and 1945 Arabian Sea tsunamis. Conclude with insights into glaciers, climate change, and debris-ice dynamics, offering a broad perspective on physics from quantum to cosmic scales.