Re: a new Yahoo Group for "Dance of the Planets"


"Greg Neill" <gneillREM@xxxxxxxxxxxxxxxxxx> wrote in message
news:eOa8e.26798$8i6.1034954@xxxxxxxxxxxxxxxxxxxxxxxx
> "Mike" <M.GS@xxxxxxxxxxx> wrote in message
news:RtT7e.49576$B12.34266@xxxxxxxxxxx

> > Are you really sure about that?
> > I assumed that if the density increase were rapid enough at some point
the
> > planets would align before their orbitals would stabilize. The effect
could
> > be simulated by adding small spheres of wood to some water then
gradually
> > have them sucked down into a slowly forming whirlpool.
>
> The gravitational field do to a spherically symmetric distribution
> of mass, as perceived outside of the sphere, depends *only* upon
> the total mass. It does not depend in any way upon the density of
> the matter.
>
> You could replace the Sun by a black hole of the same mass and the
> planets wouldn't know the difference (save for the sunlight
> disappearing some minutes later as the last of the Sun's light
> reaches each planet in turn).

If altering the Suns density would have no effect then let's go the opisite
way; what if the solar density were rapidly decreased to say the density of
styrofoam or balsa wood are you saying there would be no change in the
planetary orbits? All the demonstrations I've seen involving mass and
density to simulate the warping of space-time tell a different story. A
change in density of the mass results in changing the shape of the space
time fabric. Example; place a 3 kilogram sphere of pinewood on a *** of
elastic fabric observe how much the fabric is distorted. Then replace the
wood sphere with a 3 kilogram sphere of Lead or Iron notice how much more
sloping and distorted the fabric becomes?

Please clarify, thanks!



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