# Mechanics Goldstein again

1. May 3, 2008

### pardesi

i don't get this what he wrote...
the internal force $$\vec{F_{ij}}$$ between two particles is $$\vec{F_{ij}}=\nabla_{i} V_{ij}=\nabla_{ij} V_{ij}=-\nabla_{j} V_{ij}$$
where the subscript below $$\nabla_{k}$$implies the differentitaion with respect to components of $$\vec{r_{k}}$$
i can't get how $$\vec{F_{ij}}=\nabla_{i} V_{ij} or \vec{F_{ij}}=-\nabla_{j} V_{ij}$$
the potential energy is dependent on the relative distances between the particles hence there is no meaning to the above two equalities

2. May 3, 2008

### nonlocal

are we talking about Sheldon Goldstein?

3. May 3, 2008

### malawi_glenn

Last edited by a moderator: Apr 23, 2017
4. May 3, 2008

### nonlocal

Oh...

I was thinking about Sheldon Goldstein who deals with quantum mechanics. Sorry

5. May 3, 2008

### Staff: Mentor

Yes, you are thinking of Shelly Goldstein of Rutgers, the expert on Bohmian mechanics, not Herbert Goldstein, author of the classic textbook on classical mechanics.

6. May 3, 2008

### pardesi

oops sorry for the inconvinience that was Herbert Goldstein....

P.S:Starnge but i am not able to post with my opera 9.27(because the posting page doesn't load completely) though i am able to do so with FireFox 3 Beta 5...i use Ubuntu 8.04