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 1090 bits of data spread out over 1028cm3. We know the original apparatus had about 1019GeV (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!

1.
J. Audouze, P. Crane, T. Gaisser, D. Hegyi, J. Tran Thanh Van, eds. Cosmology and Particles, Proc. Sixteenth Rencontre de Moriond Astrophysics Meeting, Editions Frontiers (1981).
2.
J.
Audouze
,
D. N.
Schramm
,
Nature
237
,
447
(
1972
).
3.
J. Audouze, J. Tran Thanh Van, eds., The Birth of the Universe, Proc. Seventeenth Rencontre de Moriond Astrophysics Meeting, Editions Frontiers (1982).
4.
R. Balian, J. Audouze, D. N. Schramm, eds., Physical Cosmology, Proc. Les Houches Session XXXII, North Holland (1979).
5.
J.
Barrow
,
M. S.
Turner
,
Nature
298
,
801
(
1982
).
6.
A. D.
Dolgov
,
Ya. B.
Zel'dovich
,
Rev. Mod. Phys.
53
,
1
(
1981
).
7.
M. K. Gaillard, ed. Proc. 1981 Les Houches School on Gauge Theories, North Holland (1981).
8.
A. Guth, in The Big Bang and Element Creation, D. Lynden‐Bell, ed., Royal Society, London (1982).
9.
D. N. Schramm, in The Big Bang and Element Creation, D. Lynden‐Bell, ed., Royal Society, London (1982).
10.
D. N.
Shramm
,
R. V.
Wagoner
,
Annu. Rev. Nucl. Sci.
27
,
37
(
1977
).
11.
G.
Steigman
,
Annu. Rev. Nucl. Sci.
29
,
313
(
1979
).
12.
G. Steigman, in Essays in Nuclear Astrophysics, C. A. Barnes, D. D. Clayton, D. N. Schramm, eds., Cambridge U.P. (1982).
13.
A. Szalay, in Proc. 1981 Int. Conf. Neutrino Physics and Astrophysics, R. J. Cence, E. Ma, A. Roberts, eds., vol. 1, page 59, High Energy Physics Group, Department of Physics and Astronomy, University of Hawaii (1981).
14.
M. S. Turner, in Proc. 1981 Int. Conf. On Neutrino Physics and Astrophysics, R. J. Cence, E. Ma, A. Roberts, eds., vol. 1, page 95, High Energy Physics Group, Department of Physics and Astronomy, University of Hawaii (1981).
15.
M. S. Turner, D. N. Schramm, PHYSICS TODAY, September 1979, page 42.
This content is only available via PDF.
You do not currently have access to this content.