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omega comparison table

Subject	has location	has desintegration energy	is a kind of	has frequency	has quantum behavior	has wavelength	has number of quark	is an instance of	has spin	obey	has decay product	has definition	has lifetime
astronomical constant			constant
hyperon	or center of gravity	the total energy produced when the particle decays	radioactive particle	inversely proportional to the wavelength	Fermi-Dirac statistics	inversely proportional to its momentum	3		1/2 or 3/2	uncertainty principle	the products produced immediately after decay	Baryons heavier than the neutron (this term is seldom used today). They have non-zero strangeness. Free hyperons are unstable and decay into end products, one of which is a proton.	10-8 to 10-10 seconds
omega	or center of gravity	the total energy produced when the particle decays		inversely proportional to the wavelength	Fermi-Dirac statistics	inversely proportional to its momentum	3	astronomical constant	1/2 or 3/2	uncertainty principle	the products produced immediately after decay	The ratio of the average density of mass in the universe to the critical mass density, the latter being the density of mass needed to eventually halt the outward expansion of the universe. In an open universe, omega is always less than 1; in a closed universe, it is always greater than 1; in a flat universe it is always exactly equal to 1. Unless omega is exactly equal to 1, it changes in time, constantly decreasing in an open universe and constantly increasing in a closed universe. Omega has been measured to be about 0.1, although such measurements are difficult and uncertain. (See critical mass density; closed universe; flat universe; open universe.)	10-8 to 10-10 seconds

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