Lorentz force (EM), what happens if

AI Thread Summary
The discussion centers on the Lorentz force formula, questioning the implications of substituting velocity with the Lorentz factor. It is noted that this modification leads to a mismatch in dimensions and that the Lorentz force equation is considered exact as it is. Participants emphasize that the original formula effectively defines electric and magnetic fields. The inquiry was not aimed at correcting the formula but stemmed from curiosity. Overall, the conversation highlights the precision and established nature of the Lorentz force equation in electromagnetism.
fluidistic
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I'm wondering what happens (or if it makes sense) if in the formula \mathbf{F} = q (\mathbf{E} + \mathbf{v} \times \mathbf{B}) we replace v by Lorentz factor, that is \frac{1}{\sqrt{1-\frac{v^2}{c^2}}}.
I realize that in the new formula I'm cross-producting a scalar with a vector, but I could assignate a direction to Lorentz factor.

For example, would this changed formula be more accurate than the non modified one? Or does it make sense?
 
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It doesn't make sense.

Apart from the problem you identified, the dimensions no longer match. What problem are you trying to fix anyway? The Lorentz force equation is exact - often one uses it to define the electric and magnetic fields.
 
Vanadium 50 said:
It doesn't make sense.

Apart from the problem you identified, the dimensions no longer match. What problem are you trying to fix anyway? The Lorentz force equation is exact - often one uses it to define the electric and magnetic fields.

Thanks for the reply.
I wasn't trying to fix anything, it occurred to me by chance. I wasn't aware that the Lorentz force was exact, nice to know.

Thanks a lot for the information.
 
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