Pattern of research in India on theoretical astronomy and astrophysics during period 1990-1980
The most outstanding work in the field has been the theory of thermal ionisation and its application to astrophysics by Saha in early twenties. Related to it was work on pressure ionisation by Kothari in the late thirties. Although remarkable for their applications in astrophysics, both these works were basically in statistical thermodynamics. In the forties, i.e. the years immediately before independence, one finds a fairly large number of papers, notably from Calcutta and Allahabad, on the problem of pulsation of stars in different conditions, Bethe's law of energy generation and static configuration of rotating stars. There were some works on cosmology also in the pre-independence period, the interest being on the question of stability of cosmological models.
In the post-independence period, the investigations on equilibrium and pulsation of stars were continued; the notable change was the introduction of complicating factors like magnetic fields and viscosity. There was some work also on the configuration of rotating stars. In the field of cosmology, exact solutions of Einstein's equations representing situations different from the Friedmann universe as also the problem of big bang singularity attracted attention. Some interest in the red shift of light from collapsing object is also noticeable.
As the survey is confined to work done in India, a number of important contributions by Indians working outside had to be left out.
Indian Journal of History of Science, Vol. 27, no. 4 (1992).