Origin of the angular momentum

Quadibloc wrote:

The reason the Earth rotates today is that it rotated yesterday. It
*started* rotating because of the angular momentum of the material out
of which it condensed, billions of years ago. But there is no ongoing
energy input to make the Earth rotate.


BTW, everything seems to be in rotation (planets, stars, galaxies,
cluster of galaxies). Where does the original angular momentum come
from?
Is it explained by GR?

FU to sci.astro

--
Florian

"Tout est au mieux dans le meilleur des mondes possibles"
Voltaire vs Maupertuis/Leibniz/Meister