Discover the Universe's Undensity with the Human Body Calculation

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Discussion Overview

The discussion revolves around the concept of cosmological density, specifically the critical density of the Universe, and a hypothetical calculation involving the volume a human body would occupy if spread out to match this density. The scope includes cosmological theory and exploratory reasoning.

Discussion Character

  • Exploratory, Conceptual clarification

Main Points Raised

  • One participant notes that the critical density of the Universe is approximately 6 Hydrogen atoms per cubic meter and proposes a calculation involving the volume of a human body, which they estimate to be around 1 cubic meter.
  • The same participant suggests that the average molecular composition of the human body is 6.6 Carbon, indicating a specific approach to the calculation.
  • Another participant provides a rough estimate that if the human body were to be smeared out to match the critical density, it would occupy a volume of about 3 light-seconds (10^9 meters).
  • A later reply expresses a sense of disappointment or humor regarding the lack of engagement with the initial idea.

Areas of Agreement / Disagreement

Participants do not appear to reach a consensus on the calculation or the implications of the idea, and multiple viewpoints are presented without resolution.

Contextual Notes

The discussion lacks detailed assumptions regarding the calculation methods and does not clarify the implications of using different molecular compositions or densities.

Who May Find This Useful

Individuals interested in cosmology, density calculations, and conceptual explorations of the Universe's structure may find this discussion relevant.

Chaos' lil bro Order
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Greetings,

I was thinking about Cosmology and Omega-Matter. The critical density of the Universe is equal to about 6 Hydrogen atoms/ meter cubed. If we were to smear a human body out to fit it to this density, how big a volume would the human body smear out to be?

Assume, the human body occupies a volume of ~1 meter cubed

Assume, the average Mol. in the human body is 6,6-Carbon

Can anyone figure this out? It seems like a fun way to gain perspective on just how undense the Universe is.



P.S. Really our best WMAP data says the Universe's matter density is closer to 0.27 x 6 Hydrogen atoms. If we exclude dark matter, this number gets even smaller and becomes 0.04 x 6 Hydrogen atoms/ meter cubed.
 
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'any ideas folks?'
 
'A cube of side about 3 light-seconds (10^9m).'
 
'I guess no one likes this idea, lol.'
 

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