steady state theory

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun The theory describing a steady state universe.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun astronomy A cosmological model of the universe in which matter is continuously created as the universe expands

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun (cosmology) the theory that the universe maintains a constant average density with matter created to fill the void left by galaxies that are receding from each other