## biswajit_paul 3 years ago Energy or Force..Which is more fundamental? Please tell me the reason behind your answer..

• This Question is Open
1. biswajit_paul

@TuringTest @apoorvk @Vincent-Lyon.Fr help me

2. biswajit_paul

@Hero help me

3. enocrux

Energy is the ability to do work, work is force times distance, force is exerted, hope that answers your question

4. biswajit_paul

@enocrux I was thinking exactly in same way..and thought that the force should be..but still I have some confusion

5. apoorvk

Fundamental hmm - could you please elaborate what you mean to express by 'fundamental'? As in more acceptable, more physically imaginable, or more universally conservative?

6. biswajit_paul

Actually this question was asked to me. So I think that here 'fundamental' is in the sense of more acceptable and something that explains more

7. apoorvk

Let me tell you something, which you will learn soon or probably already have learnt about - everything, yes everything around you essentially,is ENERGY. Even mass is convertible into energy, (that's why the "mass-energy" conservation), as you may have studied in particle/modern physics. Force - just a means of doing work and transferring energy. Nothing else. You can also compare them through this analogy - Energy is 'what' is being transferred. Force is 'how' it's being transferred, like a medium!

8. enocrux

well id depends on the level of question, energy in some respects can be considered the most fundamental thing in the universe but in more moderate physics it would be things like mass, time, and force. things you can't readily define without twisting regular laws

9. biswajit_paul

Yes this is right. But as far as only force and energy has considered, I think apoorvk is not wrong but it is still an analogy, not a solid logic.

10. apoorvk

ofcourse not a solid logic, just as a vague analogy (only thing that I could come up with for the moment).

11. biswajit_paul

ok

12. UnkleRhaukus

energy is more fundamental, force requires multiple energies

13. Jemurray3

Frankly the question seems somewhat meaningless to me. Energy is just a quantity that is unique in that when we add all of it up, we find that the total amount of it in an isolated system doesn't change. It just changes form. Noether's theorem, generally considered one of the deepest results in theoretical physics. validates this observation by showing that the value of the Hamiltonian, which can often be associated with the total energy of a system, remains constant for those systems that do not depend explicitly on time, i.e. it doesn't matter what day of the week the experiment is performed. This lends credence to the idea that energy is fundamental, which I certainly won't argue with, but would like to point out that the proof of Noether's theorem relies on the Lagrangian formalism, the entire derivation of which is geared towards creating a system of doing physics that can easily incorporate constraints and generalized coordinates and also reproduces the Newtonian force law F = ma (or its equivalent in the relativistic case). So in that sense, without our knowledge and understanding of forces, we could not create the Lagrangian or the Hamiltonian, which is the framework for the proof of Noether's theorem and subsequently the conservation of energy. At the end of the day, we cannot experience energy directly. Our physical experiences are based on forces, and nothing else. Any influence that one thing has on another is expressed exclusively through force. Energy is a framework that we use to help us in our understanding of these forces and the behavior of systems under their influence, but at best it is a shadowy backdrop to the real star of the show. You can play with this in your mind all you like, but with regard to actually doing physics it's kind of like arguing with a waiter over whether the chicken or the egg was more fundamental when all you want is a damn omelette.

14. DLS

Energy is fundamental.

15. Carl_Pham

This is a philosophical question, not a physics question, so there are many possible answers, and their accuracy cannot be assessed by empirical test. I would say force is fundamental, because only force is directly measureable. We know from direct sensory experience whether a force is present, and how strong it is, and in what direction it points. Furthermore, every observer in every reference frame will always agree on those three facts, regardless of what else they may see as different. it's the most "real" thing in physics -- the thing the reality of which is demonstrated every day, all the time. Essentially all of physics is deduced from observations of forces and how they affect objects. So in that sense, force is more fundamental. However, it turns out that by far the most compact and efficient explanation of forces involves the energy. Although we cannot measure energy directly, if we assume its existence, we can deduce from its fairly simple nature all the things we can measure about forces. So in that sense energy is more fundamental -- because in modern physics, we tend to deduce the nature of forces from the assumed nature of energy underneath it. You might think of it as like thought and action. We cannot directly observe the thoughts of another human being. We can only infer what those thoughts might be by observing his actions. For example, we see someone scowling, answering shortly, stamping around, and infer that he is angry -- having angry thoughts. Nevertheless, once we have built up a picture of what his thoughts might be, by observing his actions, we tend to use the model we have of his thoughts to explain his further actions. For example, we'll deduce that this angry person will be unlikely to smile if we comment on a pretty bird sitting outside the window. So while actions are the more fundamental in terms of what we can observe, thoughts are the more fundamental in terms of the models we build to explain how and why people act.