Posted on 05/08/2002 7:29:49 AM PDT by Nebullis
My dear fellow, I did do as you suggested, and my head still hurts. However, nowhere in there did I find anything to back up the journalist's claim that the pull you feel when you "swing a bucket of water at the end of rope" is caused by centrifugal force, which is merely a convenient layman's notion, or so I was told in school.
More importantly, the journalist reporting on Gestheyn's findings wrote that "These [centrifugal] forces result from the combined gravitational pull of all the distant stars and planets, Austrian physicist Ernst Mach wrote." I never doubted that there is a "combined gravitational pull of all the distant stars and planets": this has always seemed a given to me because there is no range limitation to gravitational force. However, I always believed that for practical purposes, we earthlings need only take into account the gravitational force exerted by the Earth, the Sun and the Moon. What the journalist is suggesting is the exact opposite.
But as we all know, journalists never lie.
They also tell us that Clinton was a great president and that GWB is an uneducated moron, which I naturally have always taken for the gospel truth.
But if this journalist is not telling the truth then...
Oh my! Please say it isn't so.
Right, my understanding is that the force you feel is the force you exert towards the center in order to draw the bucket out of its desired straight path. Note that the direction of force (inwards) is the same as the direction of the acceleration (that being the 2nd derivative of the position as a function of time)
s(t) = ( cos(t), sin(t) )
v(t) = s'(t) = ( -sin(t), cos(t) )
a(t) = s''(t) = ( -cos(t), -sin(t) )
Sorry - couldn't help myself :-)
But for "G" to be non-invariant with respect to direction, it would seem that there would have to be a corresponding anisotropy in the matter distribution of the Universe. But as far as I know, no such anisotropy has been observed.
What gives?
I'm glad I never comitted the value of G to memory.
Sounds good to me. Things should be more scrunched up along the axis where the pull is stronger. And they're not that anyone's said so far.
It's not clear to me that an anisotropic G would lead to any anisotropy in the distribution of matter. But if it did, the matter distribution would have been used to set a limit on the anisotropy of G. Presumably this experiment was more sensitive than any existing limit, else it wouldn't have been mounted.
My thinking was that if the initial condition were an isotropic matter distribution AND an anisotropy for the gravitational constant, then one would expect over time that matter would preferentially cluster around the direction of maximum "G" value, thus resulting in a matter distribution anisotropy.
My reaction is that matter either averages somewhat denser viewed in one direction than in another or else it doesn't. But not too many people are agreeing with longshadow and me that the problem should produce so visible a result.
Perhaps the problem is that a 0.054 percent difference just doesn't model out to be enough to produce visible effects.
Anyway, the one thing people agree on is that this area needs more study. Does the max gravity perhaps lie along our galactic plane, with the peak toward the center? If not, where and what is the anisotropy producting the difference in G?
I'm having trouble visualizing that.
You want me to save the world again? I'm already fully engaged on the other thread.
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