🚀 go-pugleaf

Dear Louis_N:

<Louis_N@edu.herlufsholm.dk> wrote in message 
news:1185918231.122699.119730@19g2000hsx.googlegroups.com...
...
> Decreasing cosmic gravity.
> Here a little more about the decrease of the gravitational
> 'constant' G.

Quite an old topic (Dirac 1938)
http://www.rssd.esa.int/SA-general/Projects/GAIA_files/LATEX2HTML/node143.html

> If the age T of the Universe is assumed to be T = 15*10^9
> years then we get for the relative time decrease of G:
>
>    (dG/dT)*(1/G) = - 1/(3*T) = - 2.2*10^(-11) per year

Why linear?

> The value is near the upper limit of the relative time
> decrease of G found by analysis of different
> astronomical phenomena.

http://adsbit.harvard.edu/cgi-bin/nph-iarticle_query?bibcode=1976MNRAS.177..545H
roughly the range you come up with.

http://www.nature.com/nature/journal/v271/n5643/abs/271316a0.html
... less than 8 parts in 10^12 per year

http://arxiv.org/PS_cache/gr-qc/pdf/0511/0511072v3.pdf
http://adsabs.harvard.edu/abs/2007Ap&SS.310..173A
 six parts in 10^13 per year... about two orders of magnitude 
lower.

http://www.physorg.com/news90776642.html
... "would violate ... original theory of general relativity"

Tidal rhythmites constrains changes in G perhaps on the order of 
1 part in 10^15 per year.

Why would more recent limits on /\G show stability, even though 
expansion is "accelerating"?

David A. Smith