Astronomy   View all facts   Glossary   Help
abstraction > hypothesis > theory > astronomy theory > cosmology theory > de Sitter model
Next cosmology theory: Eddington-Lemaitre universe    Up: cosmology theory    Previous cosmology theory: cosmic string   

de Sitter model
subjectfact 
de Sitter modelis a kind of cosmology theory2001-09-27 09:34:01.0
has definition A model of the universe that contains no matter but only a positive cosmological constant. It expands exponentially forever.has source: Hawley, J.F., Halcomb, K.H. 1998 Foundations of Modern Cosmology, Oxford University Press, 2001-09-27 09:34:01.0
has definition A particular solution to Einstein's cosmological equations, found by Wilhelm de Sitter in 1917, in which space expands at a rapid, exponential rate. This solution was very different from the solutions of Friedmann and of Lemaitre, in which the universe expands at a much slower rate (a rate with the distance between any two points increasing as something between the square root of time and linearly with time). The Friedmann and Lemaitre type solutions became incorporated in the standard big bang model. Recent modifications of the big bang model, such as the inflationary universe model, propose that the universe went through a period of exponential growth, or a de Sitter phase, early in its evolution.has source: Lightman, A., Brawer, R. 1990 The Lives and Worlds of Modern Cosmologists, Harvard University Press, 2001-09-27 09:34:01.0
has definition A geometrical model (1917) of an empty universe, based on Einstein's field equations.has source: Hopkins, J. 1976 Glossary of Astronomy and Astrophysics, University of Chicago Press, 2001-09-27 09:34:01.0
cosmology theoryhas domain cosmology2001-09-27 09:34:00.0
theoryhas validity correct or incorrect with caveats2001-09-27 09:33:53.0
has author or reasearch group2001-09-27 09:33:53.0
has date or a range of dates for which the theory was active2001-09-27 09:33:53.0