Word: hydrogen
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...Cambridge Cosmologist Dennis W. Sciama explained that since the megaphysical laws are largely unknown, cosmologists must test their models against the few facts they do possess. One set of facts they are reasonably sure of: the universe "is made of a fairly uniform mixture of chemical elements; 95% is hydrogen, nearly 5% is helium formed in stars. The small remainder is the heavier elements from lithium to uranium. The elements get scarcer as they get heavier until they reach the atomic weight of 100; after that, their abundance is about the same...
...that about 5 billion years ago the universe started life with the great-great-grandfather of all explosions. The universe was then small, dense and hot, and was made up entirely of radiation and neutrons. As it exploded and expanded, most of the neutrons split into protons and electrons (hydrogen). A few joined together to form the heavier elements. It was all over in about 15 minutes; since then, the abundance of heavier elements has remained about the same...
...Cambridge cosmic model is the "steady state universe" featuring the startling principle of "continuous creation" (TIME, Nov. 20, 1950). In each several million cubic feet of space, it teaches, one atom of hydrogen is created every year. Some act of creation is unavoidable, say the Cambridge men (because the universe exists); their single assumption is much less arbitrary than assuming the creation of the whole universe jammed tightly and hotly together...
...created hydrogen atoms, says the steady state theory, the whole universe has developed. Pulled by gravitation, the hydrogen atoms clot together, forming gas clouds, stars and galaxies. The galaxies flee from one another after their own odd custom, and more hydrogen is created in the space vacated. The process continues forever without beginning...
Supernovae Impurities. When this model was first propounded, it was largely theoretical. Now, said Sciama, it is being checked against the abundances of the elements, the same set of cosmic facts that is the principal support of the explosive universe theory. Some stars made of hydrogen explode as supernovae. Their temperature and density are known roughly from observation, and they are high enough to make hydrogen atoms join together, forming all the heavier elements in about the right proportion. The explosion distributes them throughout the galaxy, and supernovae are frequent enough to supply all the heavy-element "impurities" that...