15 billion years ago, an experiment was carried out that related to the interaction between cosmology and particle physics and the unification of physics in general. This is the experiment that we call the Big Bang. It resulted in about bits of data spread out over We know the original apparatus had about (see figure 1), but, unfortunately, the graduate student who designed this equipment is no longer around, and, as a result, she can't tell us exactly what she did. So we have to try to piece together the data on our own to see if we can understand what happened in this experiment. From some of the data that we've been able to assemble—for example, from observing the 3‐K background radiation—we know the early universe was hot and dense. We also know that about one‐quarter of the isotope helium‐4. This figure is really rather amazing. The sum total of all the other heavier elements (carbon, oxygen, iron and so on) makes up less than 2 percent of the mass of the Universe. Stars make these other heavy elements, but they make them in total abundances of the order of a fraction of a percent. Yet the Universe is 25% helium‐4—and this is exactly the figure the standard theoretical model of the Big Bang predicts!
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April 1983
April 01 1983
The early universe and high‐energy physics
Many properties of the new particle field theories can only be tested by comparing their predictions about the physical conditions immediately after the Big Bang with what we can reconstruct about this event from astronomical data.
David N. Schramm
David N. Schramm
University of Chicago, Chicago, Illinois
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Physics Today 36 (4), 27–33 (1983);
Citation
David N. Schramm; The early universe and high‐energy physics. Physics Today 1 April 1983; 36 (4): 27–33. https://doi.org/10.1063/1.2915568
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