missing mass problem | has definition Poses the question: why does the Universe seem to have much more mass in it than can be seen with a telescope? Dynamical and theoretical constraints place the proportion of missing mass to be somewhere between 90-99 per cent of the total mass of the Universe. | ![has source: Clark, S. 1997 Towards the Edge of the Universe, Wiley, 2001-09-27 09:34:06.0 has source: Clark, S. 1997 Towards the Edge of the Universe, Wiley, 2001-09-27 09:34:06.0](facet.gif) |
has definition The cosmic mass that some scientists hypothesize so that the universe will have the critical density of matter, with an exact balance between gravitational energy and kinetic energy of expansion. Such mass is called missing because it represents about 10 times as much mass as has actually been detected. (See closed universe; critical mass density; dark matter.) | ![has source: Lightman, A., Brawer, R. 1990 The Lives and Worlds of Modern Cosmologists, Harvard University Press, 2001-09-27 09:34:06.0 has source: Lightman, A., Brawer, R. 1990 The Lives and Worlds of Modern Cosmologists, Harvard University Press, 2001-09-27 09:34:06.0](facet.gif) |
is an instance of problem | ![2001-09-27 09:34:06.0 2001-09-27 09:34:06.0](facet.gif) |