Assuming a Hubble constant of 74.3 km/sec/Mpc, the critical density is about E-29 gm/cm3. To calculate observable matter based on 5% of this density (the other 95% is dark matter and dark energy), a volume has to be used. But which volume, the one with a 13.7 billion light year radius or the approximate 45 billion light year radius of the expanded universe?(adsbygoogle = window.adsbygoogle || []).push({});

The two results vary by 39 times, 4.6 x E54 gm or 1.8 x E56 gm.

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# Critical density and total observable mass

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