Force fields and law of conversation of energy

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Discussion Overview

The discussion revolves around the relationship between force fields (magnetic, electric, and gravitational) and the law of conservation of energy. Participants explore whether the existence of these fields constitutes a violation of this law, examining the nature of energy in relation to these forces.

Discussion Character

  • Debate/contested
  • Conceptual clarification

Main Points Raised

  • Some participants question why force fields would be considered a violation of the law of conservation of energy.
  • One participant reflects on their initial question, suggesting it may be illogical since these forces arise from potential energy gained by objects.
  • Another participant proposes that energy results from the interaction of these forces with objects, rather than the forces being derived from energy.
  • A later reply asserts that the forces on particles in a field arise from the derivatives of coupling terms, specifically referencing the gradient of potential energy in classical field theory.
  • Another participant notes that dynamic fields possess energy and momentum, which, when combined with the energy and momentum of matter fields, are conserved if all interactions are mediated by the field.

Areas of Agreement / Disagreement

Participants express differing views on the relationship between force fields and energy conservation, indicating that multiple competing perspectives remain without a clear consensus.

Contextual Notes

Some statements depend on specific definitions of energy and force fields, and the discussion includes unresolved aspects of classical field theory.

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Why aren't force fields such as magnetic, electric and gravitational fields considered as a violation to law of conversation of energy?? :confused:
 
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Why would they be?
 
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.
 

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