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Old 28-April-2008, 03:54 AM
Jeff Root Jeff Root is offline
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Join Date: Dec 2004
Location: Minneapolis
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The computer program doesn't blow up at the edge, since it is
calculating over clumped points within the disk instead of a mass
spread evenly throughout the disk, as with an integration. However,
as I make the thickness of the disk smaller and smaller, the gravity
at the edge climbs higher and higher.
That should make the problem much easier to resolve than if it only
showed up when it reaches zero thickness. This way, you will get
a definite indication that you have found the problem and fixed it,
rather than applying some arbitrary restriction which makes the
infinities go away but doesn't necessarily give correct results.

Quote:
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With zero thickness, the particle does not lie against a surface as it
would with a sphere or thick disk.
I don't understand the geometry you are describing when you say
"...lie against a surface...".

Quote:
Originally Posted by grav View Post
Since the force varies with the square of the distance, we might need
two dimensions to cancel out the infinities.
I think you shouldn't be producing infinities in the first place. Cancelling
them out sounds like a hack, and a particularly dangerous one.

-- Jeff, in Minneapolis
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