The Abundance of Deuterium A Check on Big Bang

The last parameter of big bang nucleosynthesis. .. is being pinned down by measurements of the deuterium abundance in high-redshift hydrogen clouds. 

It is always risky to identify the origin of an idea. The basic idea of the Big Bang may be identified with the Russian mathematical physicist, Alexander A. Friedmann, who in 1922, armed with Einstein s general relativistic equations, developed the picture of the universe expanding from a point origin. The timing was wrong, 

In the same year that the a y paper was published, another cosmological scheme was proposed to account for the presently observed universe. The architects of this theory were Fred Hoyle, Hermann Bondi, and Thomas Gmld from Cambridge University, who developed it in two papers pubfished in 1948. This theory, called the steady state theory, was the polar opposite of the big bang. Whereas the big bang posited a definite beginning and ongoing evolution, the steady state theory was based on what can be 

Of course, any cosmology must account for facts such as the observed expansion of the universe. In the face of this incontrovertible observation, steady state theorists had to find a way to keep matter from thinning out as the expansion occurred and to maintain a constant density of matter over time. To do this they made a bold and unfounded basic assumption they assumed that hydrogen atoms are continuously created throughout all of space. To match the observed expansion and to maintain a constant density of matter, about one hydrogen atom must appear in each and every cubic meter of space every 300,000 years. 

A second fact that conftonted cosmologists in the 1960s was the discovery of a radiation that permeated the universe. This radiation, called microwave background radiation, had been predicted in 1948, but the prediction attracted little to no attention. In fact. 

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