Lecture 17 - Quantum Stars

The discoveries made by a young man from Madras, and the implications thereof, shook some of high priests of Astrophysics in the early 1930s. S Chandrasekhar, working for his Phd at Trinity College, Cambridge not only found the answer to the stability of stars, his calculations also clearly hinted at the ultimate collapsed state of stars! Ultimately this would herald the era of high energy astrophysics in the form of supernovae, neutron stars and black holes.

By 1923, the stability of stars was well understood. Stars are stable because the inward pull due to gravity is balanced by the combined pressure of gas and radiation. What will happen to a star when it is no longer able to generate heat? This was the question confronting astronomers when a highly dense star, with a density of a million grams per cubic centimetre, was discovered in 1925. Around the same time, great discoveries were being made in the new Quantum Theory of matter. This lecture tells the story of how Fowler (in Cambridge) and young Subrahmanyan Chandrasekhar (a young college student) answered this question by invoking the new quantum theory. This lecture will also discuss the truly revolutionary discovery by Chandrasekhar in 1930.