Einstein's acceleration

<blockquote id="quote"><font size="2" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by johnduff</i>
<br />Casual inspection of the equation indicates that under some conditions (small values of r), the sign of "A" changes from minus to plus. (Repelling Gravity instead of attracting?)<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">No. The approximation quoted is only valid for weak-field, low-velocity cases such as "planets in the Sun's field", as the paper indicates. For strong-field cases (such as small values of r), one must include additional terms that were neglected in the first-order-in-potential approximation shown. But only the first order was needed to make the argument in the paper. -|Tom|-

Thank you Tom.

I was afraid that my question was a conceptual one, which can be very frustrating for both the teacher and the student alike.

If you wish, you can strike the question and the answer from your message board. I am completly satiafied with your answer and see no reason for expanding the conversation.

I do have further questions re Gravity, but they belong in a different place.

John Duff