a) In 1917 Einstein applied his theory of general relativity
in the universe, and suggested a model of a homogenous, static,
spatially curved universe. . . . He then fiercely resisted
the view that the universe was expanding, despite his
contemporaries' suggestions that this was the case.
b). . . . in 1927, Georges Lemaître,
. . . concluded that the universe was expanding by combining
general relativity with astronomical observations.
Yet, Einstein still refused to abandon his static universe.
c) However, in an April 1931 . . .Einstein finally adopted
a model of an expanding universe.
d) In 1932 he teamed up with the Dutch theoretical physicist
and astronomer, Willem de Sitter, to propose an eternally
expanding universe which became the cosmological model
generally accepted until the middle of the 1990s.
e) Later Lemaître's idea became known as the "Big Bang theory''.
Was " Hot Big Bang theory'' created from the GRT or vice versa?