Brendan wrote:Regarding angular momentum, I wonder if all of the
macroscopic angular momentum in the universe adds up to zero, with
stuff that spins one way having their spin canceled out by other matter
that spins in other directions.
It is though interesting to observe that the total angular momentum of
our "observable universe" (which we generaly call just "the universe")
does not need to add up to zero. Beyond our local horizon (which is a
sphere of comoving radius, Fridger surely knows more than me about this),
beyond, I was saying, lies almost surely more stuff. Lots and lots of
"unobservable universe", causally disconnected from ours. Spinning bits
"there" may well cancel the angular momentum of spinning bits "here".
In any case, the angular momentum of the observable universe is
probably something that can be measured, in principle. It would be
"dizzy" to have t adding to something non-zero!
Now, the total angular momentum of the "whole" universe? Ahhh!
Guillermo