RJH: So what is meant by a continuous distribution of matter? A continuous distribution implies homogeneity in some sense.

Incorrect. In this case the word "continuous" refers to a mathematical property, not a physical property. The equation that describes the distribution of matter must be continuous (i.e., must have no embedded infinities) in order to be integrable. As an example, the equation y=x^2 is continuous, because all finite values of "x" produce finite values of "y". However, the equation y = 1/(x-1)^2 is not continuous, because x=1 provides an undefined 1/0 (infinity) for "y". The word "continuous" means only that the distribution of matter must meet this mathematical definition of continuity.

<font size=-1>[ This Message was edited by: Tim Thompson on 2002-06-21 17:24 ]</font>