Force fields and law of conversation of energy

Join the discussion
Registration is free. Start your own thread to ask a follow-up.
5 replies · 2K views
Entanglement
Messages
438
Reaction score
13
Why aren't force fields such as magnetic, electric and gravitational fields considered as a violation to law of conversation of energy?? :confused:
 
Physics news on Phys.org
Drakkith said:
Why would they be?
After I wrote the topic It came on my mind that my question is illogical since all these forces arise due to the potential gained by the body.
 
Actually I think energy is the result of these forces interacting with objects, not the other way around.
 
Drakkith said:
Actually I think energy is the result of these forces interacting with objects, not the other way around.

No, the OP had it correct. Given a field, the forces on particles coupling to the field arise from derivatives of the coupling term(s). In the simplest cases (e.g. EM), this would be (minus the) the gradient of the potential energy. A more general treatment can be found in the formalism of classical field theory.
 
The fields themselves have energy and momentum (dynamic fields anyways), this combined with the energy and momentum of the matter fields is conserved assuming all interactions are mediated by the field.