Earlier I tried, with less skill than one might have hoped, to explain that
it is possible to imagine a 100% Newtonian expanding universe.
If you say it carefully, it's true. It suffices to imagine a universe
where things adhere strictly to the Hubble law: velocity proportional to
I think this is important for pedagogical reasons, to de-mystify the basic
At 03:04 PM 2/12/01 -0500, David Bowman quite correctly pointed out that in
our non-imaginary universe we have additional observations; among other
things, we can observe deviations from the Hubble law.
He also pointed out that a nonzero value of the Cosmological Constant is
Questions for David: What value of the CC do you think is right? How well
established is this value? With what confidence can values with the
opposite sign be excluded? (The last time I knew, if you asked 3
astronomers you would get 5 different CC values, and you could get several
more if you asked them again a year later.)