The theory describing a steady state universe.
A theory of cosmology, no longer favored, holding that new matter is continuously being created, thus keeping the density of the expanding universe constant.
A cosmological theory stating that the universe has always expanded at a uniform rate with no beginning or end, that it will continue to expand and have constant density, and that the distribution of old and new objects in the universe is basically even. The theory has been largely abandoned in favor of the big bang theory, largely due to the discovery of quasars and other entities that appear only at very great distances, suggesting an absolute relationship between the age of objects and their distance. Steady state theory was also discredited by the discovery of cosmic background radiation , which was predicted by the big bang theory but not by the steady state theory.