Physics
Could all of humanity fit in a sugar cube?
Atoms are mostly empty. Squeeze every human on Earth to the density of an atomic nucleus and all 8 billion of us would fit in about 2 cubic centimetres, the size of a sugar cube.
Source: Nuclear density about 2 × 10¹⁷ kg/m³.
Context
If you removed the empty space, yes. Almost all of an atom's mass sits in its nucleus, which is tiny compared with the whole atom. At nuclear density, around 2 × 10¹⁷ kg per cubic metre, the mass of 8 billion people takes up about 2 cubic centimetres.
Nothing on Earth can do this compression; only neutron stars reach that density. The point is how empty matter is. The solid-feeling world is electromagnetic forces holding mostly nothing apart.
This fact sits next to the height test. See where you land.
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