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The Question

(Submitted March 28, 1997)

Given the latest value of the Hubble constant at 60-65 Km/s/Mpc and assuming a zero cosmological constant how do you actually calculate the age of the Universe ?

The Answer

Here is a short answer to a complicated problem. One can estimate the age of the Universe from the Hubble constant and the "deceleration parameter", which in turn depends on the energy densities in the Universe (usually expressed as Omega and Lambda). The article at

shows the variation in the age of the Universe with H and Omega - see especially the discussion associated with Figure 2.

Jim Lochner & Koji Mukai
for Imagine the Universe!

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