3.1 Sspd chapter 1_part 1_appendices of disoverers and inventors  (Page 4/8)

Ralph Fowler used Fermi-Dirac Satistics to explain the degeneracy pressure of electrons which helps prevent further collapse of White Dwarf after the fusion reaction fuel is exhausted. Fowler calculated that for a given composition, matter density of white dwarf was proportional to square of the mass. But this led to the impossible propostion that if the mass of a dying star (where all the hydrogen has ben used up) was 1.4Mo (where Mo is the mass of our Sun) or greater, then density tends to become infinity.

S. Chandrashekher used Special Theory of Relativity to explain the state of matter if the mass of the dying star exceeded 1.4Mo and concluded that if star is heavier than 1.4Mo then super-nova explosion takes place and the star collapses into neutron star and the degeneracy pressure of neutrons prevents the further collapse of the netron star.

In 1935, he presented his finding to Royal Astronomical Society but his own mentor and research guide Arthur Eddington denounced as Stellar Buffonery. S. Chandrashekher was dejected and crest fallen. He moved to an Academic Position in Chicago University in the year 1937. In 1939 he published his monograph on Stellar Structure including his findings on neutron star.

In 1939 J. Robert Oppenheimer and his student Hartland Snyder wrote a joint paper “On Continued Gravitational Collapse”. In this paper General Theory of Relativity was applied to explain the state of matter and it was given the name of Black Hole. It was conjectured that if star is heavier than 3Mo then even the neutron degeneracy does not stop the collapse. Now matter is a newer form called Black Hole which leads to countering the gravitational collapse.

It was clearly shown that there was no such thing as peaceful equilibrium. The criteria of equilibrium was continuously changing. We are essentially in a violent world.

Fritz Zwicky observed supernove explosions and identified them as the explosions which dying stars experience when Mass of the star exceeds 1.4Mo. When mass is below 1.4Mo then it experiences only nova explosion. Supernova exploding stars were regarded as standard candle for measuring the distances of galaxies. Fritz Zwicky also recognized the dark matter whose gravitation dominates the dynamics of large scale structure.

Arthur Edington and Edward Arthur Milne rejected Chandrashekeher’s conjecture of 1.4Mo. Similarly Edwin Huble and Walter Baade a close colleague of Fritz Zwicky rejected the conjecture of Zwicky that of a violent Universe.But finally both S.Chandrashekher and Zwicky were vindicated.

In 40’s S. Chandrashekher offered a course on elementary particles for Yerkes University for which he used to drive down 100miles from Chicago University. But his class in this course consisted of only two students. He considered this worth the effort and eventually in 1957 his belief was vindicated. His both the students Chen Ning Yang&Tsung Dao Lee shared the Nobel Prize in Physics in 1957 for their penetrating investigations in the parity laws. The Universe is just wee bit asymmetrical as a result there are instances of parity law violations. This has far reaching consequences for Elementary Particle Physics.