The Triplet Paradox

On Monday, October 2, 2017 at 12:28:49 PM UTC-7, The Starmaker wrote:
The Starmaker wrote:

Sylvia Else wrote:

Okay, if you have just one planet in the whole universe...
and either the planet is standing still or moving in a straight line
forever..

are there any forces involved here?

There are the forces within the planet, but otherwise no.

Sylvia.

So, the planet is moving along a straight line and a second body appears near by..

what happens now? doe the force "within the planet" grab the second body??

What second body? You specifically stated that "you have just one planet in the whole universe..."

So, you are changing the 'givens' in mid-stream...

I mean, when does gravity enter the picture?

If you have a body containing mass, gravity is always in the picture.