- #1

zhermes

- 1,255

- 3

1) "despite cosmological expansion, small-bound objects do not expand."

and further,

2) "things like galaxies will aways remain bound, and will not expand."

Pertaining to 1)

Because cosmological expansion is a coordinate property, don't small scale objects still expand? I.e. at redshift ~ 1, was a ruler half the size? an electron's orbital separation?

Pertaining to 2)

If expansion is accelerating, and if---in particular---that expansion is beginning to grow exponentially (Friedman's equation for cosmological-constant dominated universe), won't all objects become unbounded eventually?

Is there a(n easy) way of expressing coordinate expansion as an effective force?