Can the Lorentz Force be understood non-relativistically?

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SUMMARY

The Lorentz force, defined as $$\vec{F} = q\vec{v} \times \vec{B}$$, cannot be fully understood without the framework of special relativity. The discussion highlights that the velocity in the Lorentz force must be measured in the same inertial frame as the electric field (E) and magnetic field (B), as emphasized in Purcell's text. Prior to relativity, physicists operated under the assumption of a luminiferous aether, which defined a preferred reference frame for electromagnetism. The inconsistency between Newtonian mechanics and Maxwell's equations necessitated the development of special relativity, proposed by Albert Einstein in 1905.

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  • Understanding of electromagnetism concepts, specifically the Lorentz force.
  • Familiarity with special relativity principles and Lorentz transformations.
  • Knowledge of Maxwell's equations and their implications in classical physics.
  • Basic grasp of reference frames in physics.
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  • Study the derivation and implications of Maxwell's equations in classical electromagnetism.
  • Learn about Lorentz transformations and their application in special relativity.
  • Examine the historical context of the luminiferous aether and its role in the development of modern physics.
  • Explore the differences between classical and relativistic mechanics, particularly in high-velocity scenarios.
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Students and professionals in physics, particularly those focusing on electromagnetism and relativity, as well as educators seeking to clarify the relationship between these fundamental concepts.

RiemannLebesgueLemma
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I'm not sure if this belongs in special/general relativity or in this subforum.

I'm currently trying to refresh and strengthen my E&M, and I remembered that one thing that bugged me when I first learned about magnetism was the velocity in the Lorentz force,
$$\vec{F} = q\vec{v} \times \vec{B}$$.
It wasn't really clarified in the lecture video that I was watching, nor in my first-year E&M class, which reference frame this is valid in. I asked my professor at the time, and he gave me quite an unsatisfactory answer. My thinking was that, since E&M was developed before relativity, we should be able to understand this velocity in a non-relativistic context; this leads to some paradoxes, since, for example, we could entirely null the effect of a neutral wire on a moving charge just by boosting to the frame with the velocity of the charge carriers in the wire. If we don't consider Lorentz transformations, then the moving charge in the new frame sees only a neutral wire with no current, and thus should feel no force.

This led me to come to the kind of independent conclusion that the force can only be understood in a relativistic context, and that the full force,
$$\vec{F} = q(\vec{E} + \vec{v} \times \vec{B})$$
measures velocity in a frame relative to that in which we measure E and B.

This makes sense to me, but it doesn't seem like it is really highlighted in either Jackson or Griffiths. Purcell, after stating the force law, does stress that F, E, B and v must all be measured in the same inertial frame. Purcell also mentions in its introduction that Lorentz was close to the theory of relativity in his work on moving charges, which seems to suggest that this problem of velocity-dependence was one of the motivating factors for relativity.

Is it true that we can only understand the Lorentz force within the framework of special relativity? Also, if so, how did they account for magnetic forces before relativity?
 
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RiemannLebesgueLemma said:
This led me to come to the kind of independent conclusion that the force can only be understood in a relativistic context, and that the full force,
$$\vec{F} = q(\vec{E} + \vec{v} \times \vec{B})$$
measures velocity in a frame relative to that in which we measure E and B.
In the pre-relativity days, physicists assumed the existence of a medium (the luminiferous aether) that defined a preferred reference frame for electromagnetism. My understanding is that ##\vec v## was assumed to be measured relative to the aether.
 
Maxwell's equations did come before relativity. One can say special relativity was Einstein's solution to the riddles created by Maxwell's Equations.

https://en.wikipedia.org/wiki/Special_relativity said:
It was originally proposed in 1905 by Albert Einstein in the paper "On the Electrodynamics of Moving Bodies".[1] The inconsistency of Newtonian mechanics with Maxwell's equations of electromagnetism and the lack of experimental confirmation for a hypothesized luminiferous aether led to the development of special relativity, which corrects mechanics to handle situations involving motions at a significant fraction of the speed of light (known as relativistic velocities).
 
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