🚀 go-pugleaf

On 31 Jul., 03:43, "N:dlzc D:aol T:com \(dlzc\)" <d...@aol.com> wrote:
> Dear Louis_N:
>
> <Loui...@edu.herlufsholm.dk> wrote in message
>
> news:1185835609.115111.188660@d55g2000hsg.googlegroups.com...
>
> > The Accelerating Universe and Decreasing Cosmic
> > Gravity.
>
> > By Louis Nielsen, Denmark    http://www.rostra.dk/louis
>
> > The discovery of the accelerating Universe could be an
> > indication of a cosmic decreasing gravity.
> > Observations of supernovae, belonging to distant
> > galaxies, show that they are situated at distances that
> > are greater than what would be expected according to
> > current cosmological models.
>
> Their source characteristics, explosion, and duration is also
> controlled by G.  The fact they are recognizeable to a z of about
> 5 says you are barking up the wrong tree.
>
> ...
>
> > The decrease of G with cosmic time is (in the continuous
> > approximation) given by the equation:
>
> > (1)   (1/G)*(dG/dT) = - (1/3)*(1/T)   (dG/dT is the time
> > derivative)
>
> The value of G has been constant to a very high order (something
> like 1 part in 10^8) over the last 2.2 billion years, with tidal
> rhythmites.
>
> I'd bet that G isn't as constant or fundamental as we'd hope, but
> I would guess that it averages to a local "constant".
>
> David A. Smith

Decreasing cosmic gravity.
Here a little more about the decrease of the gravitational 'constant'
G.

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

The value is near the upper limit of the relative time decrease of G
found by analysis of different astronomical phenomena.
It must be noticed: The gravitational 'constant' G is the least-well
measured fundamental constant in physics. And different cosmological
models give different values of the age of the Universe.

References:
Viking landers:
(dG/dT)/G < 10^(-11) per year
(Chandler et al.: Bull. Am. Astron. Soc. 25 (1993), 1233)

Pulsar orbits:
(dG/dT)/G < 10^(-11) per year
(Kaspi et al.: Astrophys. J. 428 (1994), 713)

Cooling of white dwarf:
(dG/dT)/G < 4*10^(-11) per year
(Garcia-Berro et al.: Mon. Not. R. Astron. Soc. 277 (1995), 801)

White dwarf astroseismology:
(dG/dT)/G < 4*10^(-11) per year
(Benvenuto et al.: Phys. Rev. D 69 (2004))

Best regards
Louis Nielsen
Denmark

http://www.rostra.dk/louis