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Cosmology: The Study of the Universe

Cosmology is the scientific study of the large scale properties of the universe as a whole. It endeavors to use the scientific method to understand the origin, evolution and ultimate fate of the entire Universe. Like any field of science, cosmology involves the formation of theories or hypotheses about the universe which make specific predictions for phenomena that can be tested with observations. Depending on the outcome of the observations, the theories will need to be abandoned, revised or extended to accommodate the data. The prevailing theory about the origin and evolution of our Universe is the so-called Big Bang theory.

Choose from the links in the left column for discussed at length.

This primer in cosmological concepts is organized as follows:

  • The main concepts of the Big Bang theory are introduced in the first section with scant regard to actual observations.
  • The second section discusses the classic tests of the Big Bang theory that make it so compelling as the most likely valid and accurate description of our universe.
  • The third section discusses observations that highlight limitations of the Big Bang theory and point to a more detailed model of cosmology than the Big Bang theory alone provides. As discussed in the first section, the Big Bang theory predicts a range of possibilities for the structure and evolution of the universe.
  • The final section discusses what constraints we can place on the nature of our universe based on current data, and indicates how WMAP furthers our understanding of cosmology.
  • In addition, a few related topics are discussed based on commmonly asked questions.

For purposed of citation of this portion of the site or the downloadable PDF you can use this information:

WMAP Science Team, "Cosmology: The Study of the Universe," 
NASA's Wilkinson Microwave Anisotropy Probe,last modified June 6, 2011,

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  • Page Updated: Friday, 12-21-2012