Is the Strong Force Really Stronger Than the Electromagnetic Force?

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Discussion Overview

The discussion centers on the comparison of the strong force and the electromagnetic force, particularly in the context of a helium nucleus. Participants explore how to determine which force is stronger and the implications of their interactions within atomic structures.

Discussion Character

  • Debate/contested
  • Conceptual clarification
  • Technical explanation

Main Points Raised

  • One participant questions how the strong force can be considered stronger than the electromagnetic force when protons in a helium nucleus appear to be in equilibrium, despite their repulsive electromagnetic interaction.
  • Another participant suggests that the distances over which the forces act are crucial to understanding their relative strengths.
  • A different viewpoint emphasizes that protons do not move closer together due to stable states and the Pauli exclusion principle, which prevents identical fermions from occupying the same state.
  • It is noted that the electromagnetic force increases with the number of protons, while the strong force is short-range, leading to the conclusion that the strong force must dominate at smaller scales until many protons are present.
  • One participant introduces the concept of motion and the Uncertainty Principle, suggesting that while average positions of nucleons must be stable, they must also be in motion relative to each other.
  • A historical reference is made to early attempts at predicting nuclear energy using electromagnetism, highlighting that electromagnetism may have more influence than commonly perceived.

Areas of Agreement / Disagreement

Participants express differing views on the nature of the strong and electromagnetic forces, with no consensus reached on how to definitively compare their strengths in the context of nuclear interactions.

Contextual Notes

Participants discuss various assumptions regarding the behavior of forces at different scales and the implications of quantum mechanics, but these assumptions remain unresolved within the discussion.

PhDnotForMe
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So I am aware that the strong force is the strongest force with the electromagnetic force being the second strongest force. I am wondering how we go about the process of deciding which force is stronger.
I am visualizing a helium nucleus; two protons, two neutrons. The two protons are pushing away from each other with the electric repulsive force, while there is a strong force connection between each of the hadrons. It seems to me that because the protons are neither moving away nor moving towards each other, the electromagnetic force and strong force are in equilibrium. If this is true how can it be claimed the strong force is stronger than the electromagnetic force. I believe I read somewhere that it is 137 times stronger. Would love an explanation about this!
 
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does this help ...

Four-Fundamental-Forces.gif
Fundamental-Forces.jpg
note the distances over which they act
 

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PhDnotForMe said:
It seems to me that because the protons are neither moving away nor moving towards each other, the electromagnetic force and strong force are in equilibrium.

There's a misunderstanding here. The protons don't move towards or away from each other because they are in stable or metastable states. Much like how electrons exist in atomic orbitals and neither move away from or towards the atom. They would certainly move closer in towards the nucleus if they could, but such a lower energy state either doesn't exist or is already filled by other electrons. The laws of nature apparently forbid fermions from occupying identical states, and it is this that keeps both protons from moving closer together as well.

One thing to notice is that the repulsive force from protons on each other increases as you add more and more protons, and this happens without limit because the range of the EM force is infinite. However, the strong nuclear force (the residual part of the color force to be more specific) is very short range, and only a handful of nucleons will attract each other via it. So it must be the case that the strong nuclear force is overwhelming the EM force until you gather together dozens and dozens of protons. Otherwise we would see stable light nuclei falling apart as soon as you add a couple of protons together.
 
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The average positions must be stationary, otherwise the system would fall apart, but equally the nucleons must be in motion with respect to each other, otherwise one would have a fixed position is a frame of reference defined by the others and hence zero momentum in that frame, which violates the Uncertainty Principle. If we assume an underlying Lagrangian (which the standard model has) and some form of function for the potential energy, then the viral theorem defines a relationship between kinetic and potential energies for bound states. For those interested in oddities, the first theoretical attempt at predicting the nuclear energy relied on electromagnetism, and it got the energies fairly well up to oxygen (Volochine, F. E. 1925. C. R. des Séances de la Société Polonaise de Physique, Fasc V.: 61 – 73.) Additionally, he correctly predicted the spin magnetism of the yet to be discovered neutron. While this was wrong because he needed the proton and neutron to be about 6-7 times smaller than they actually are, this work showed that electromagnetism can have more effect than most think. Since this is not the place for speculative theories, one cannot go further here, but it may not be totally impossible to go further.
 
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