NASA Trying to Prove Big Bang Theory Despite Newton

"They're going out, theory in hand, selecting data which might support their belief.
According to Newton, and Charles Sanders Peirce, that's not proper scientific method."―Dan Mahony

NASA Says:

The Big Bang Theory is a broadly accepted theory for the origin and evolution of our universe. It postulates that the observable universe started from an instantaneously expanding point, roughly ten to twenty billion years ago.

Foundations of the Big Bang Theory

The hot Big Bang Theory is a broadly accepted theory for the origin and evolution of our universe. It rests on two seeming sound pillars:

• The General Theory of Relativity: Over eighty years ago, Einstein proposed this theory that describes how the distribution of mass in the universe determines the geometry of the space. Originally, the theory was able to account for peculiarities in the orbit of Mercury and the bending of light by the Sun. In recent years, the theory has passed a series of rigorous tests.
• On the largest scales, the distribution of matter in the universe is nearly uniform. This assumption appears to confirmed both by galaxy surveys and by the low level of fluctuations in the cosmic microwave background radiation

In the hot Big Bang Theory, the observable universe began with an instantaneously expanding point, roughly ten to twenty billion years ago. Since then, the universe has continued to expand, gradually increasing the distance between our Galaxy and external galaxies. The expansion of the universe "stretches" light rays converting blue light into red light and red light into infrared light. Thus, distant galaxies, which are rapidly moving away from us, appear redder. This expansion also cools the microwave background radiation. Thus, the cosmic microwave background radiation, which today has a temperature of 2.728 Kelvin, was hotter in the early universe. Gravity slows the expansion of the universe. If the universe is dense enough, the expansion of the universe will eventually reverse and the universe will collapse. If the density is not high enough, then the expansion will continue forever. Thus, the density of the universe will determine its ultimate fate.

Tests of the Big Bang Theory

The hot Big Bang Theory is consistent with a number of important observations:

• the observed expansion of the universe,
• the observed abundances of helium, deuterium and lithium, three elements thought to be synthesized primarily in the first three minutes of the universe,
• the thermal spectrum of the cosmic microwave background radiation
• the cosmic microwave background radiation appears hotter in distant clouds of gas. Since light travels at a finite speed, we see these distant clouds at an early time in the history of the universe, when it was more dense and thus hotter.

Beyond the Big Bang Theory

In its current form, the big bang theory is not complete. It does not explain:

• the origin of galaxies and the observed large-scale clustering of galaxies
• the origin of the uniform distribution of matter on very large scales

Many cosmologists suspect that the Inflation Theory, an extension of the Big Bang Theory, may answer these questions.

Further Reading

• Peebles, P.J.E., Schramm, D.N., Turner, E.L. \& R.G. Kron 1991, "The Case for the Relativistic Hot Big Bang Cosmology", Nature, 352, 769 -- 776.
• Peebles, P.J.E., Schramm, D.N., Turner, E.L. \& R.G. Kron 1994, "The Evolution of the Universe'', Scientific American, 271, 29 -- 33.
• Will, Clifford, "Was Einstein Right?"

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Last updated: Friday, 05-21-1999