|
|
|
|
|
|
by blix
2422 days ago
|
|
|
The gravitational forces at the center do cancel out, but the important term for this effect is not the sum of forces but the gravitational potential, essentially the energy gained/lost by moving from deep space to the given location. Force is the derivative of this potential, so the abscence of forces in the center indicates an extremum. |
|
|