# B Gravitational Filed and Particles

1. Oct 15, 2016

### kent davidge

(Sorry for my bad English.) Suppose we choose the surface of the Earth at a point as having a zero potential energy. Now if there're two particles of equal mass at rest, one of them just an heigh above the another, the one which is at the ground will not have potential energy. Since the particles are at rest, their energy would be equal to mc². Since the particle above the ground will have a greater energy, it would have a greater mass. Then is it correct to say that the gravitational field gives mass to the particle in that situation?

2. Oct 15, 2016

### jbriggs444

The gravitational potential energy (or lack of a deficit thereof) would best be regarded as part of the Earth-particle system rather than as intrinsic to the particle. No matter where it is, the particle's mass remains the same. However, an Earth-particle system with particle higher will have a tiny bit more mass than an Earth-particle system with the particle lower.

3. Oct 15, 2016

### kent davidge

So would this mean that the Higg's field is not the only field that gives mass to particles?

4. Oct 15, 2016

### jbriggs444

I do not have the requisite competence to accurately unravel this mixing of models.

Gravitational potential energy is a concept from classical mechanics. $E=mc^2$ is a concept from Special Relativity. The notion of gravitational potential energy is already on shaky ground when one models gravitation according to General Relativity. If one then insists on speaking of mass as arising from the Higgs field, that's yet another model. To speak of mass as arising from the one thing or the other seems to me to be a false dichotomy. But perhaps someone with better insight into GR and the Higgs mechanism can speak up.

Last edited: Oct 16, 2016
5. Oct 16, 2016

### jartsa

No. Forces create composite particles, which interact with the Higg's field, with some strength of interaction.

A composite particle composed of one planet and one rock bound together by gravity interacts weakly with the Higg's field, compared to a planet and rock far away from each other.

There may be some mixing of models in that above text. But this seems to be free of such thing:

A composite particle composed of two protons, bound together by nuclear force, interacts weakly with the Higg's field, compared to two protons far away from each other.

Last edited: Oct 16, 2016