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Hubble time
(H0-1)
subjectfact 
Hubble timehas symbol H0-12001-09-27 09:32:59.0
has value 10 to 20 billion yearshas source: Guth, A.H. 1997 The Inflationary Universe, Addison-Wesley, 2001-09-27 09:32:59.0
has definition The Hubble time is one divided by the Hubble constant, which gives a number from 10 to 20 billion years. For a flat universe with no cosmological constant, the age of the universe is two-thirds of the Hubble time.has source: Guth, A.H. 1997 The Inflationary Universe, Addison-Wesley, 2001-09-27 09:32:59.0
has definition The inverse of the Hubble constant and a crude measure of the universe's age. For a Hubble constant of 50, one can calculate that the Hubble time is 19.6 billion years; for a Hubble constant of 80, the Hubble time is 12.2 billion years. If there is no cosmological constant, the universe is younger than the Hubble time. In particular, if the mass density of the universe (designated Ω) is 0.1, the universe's age is 90 percent of the Hubble time; if Ω is 1.0, the universe's age is 67 percent of the Hubble time.has source: Croswell, K. 1995 The Alchemy of the Heavens, Anchor Books, 2001-09-27 09:32:59.0
is an instance of astronomical constant2001-09-27 09:32:59.0
is an instance of time2001-09-27 09:32:59.0
timehas unit time unit2001-09-27 09:33:25.0