OK FINE, magnetism is explained away by relativity

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    Magnetism Relativity
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Discussion Overview

The discussion revolves around the relationship between magnetism and relativity, particularly focusing on induced current and the transformation properties of electric and magnetic fields under Lorentz transformations. Participants explore theoretical implications and the nature of these fields in different frames of reference.

Discussion Character

  • Exploratory, Technical explanation, Debate/contested

Main Points Raised

  • One participant questions the nature of induced current in the context of relativity, expressing confusion about the topic.
  • Another participant suggests that certain configurations of electric and magnetic fields, specifically those dependent on the sign of E^2 - B^2, cannot be transformed into purely electric configurations through Lorentz transformations.
  • A further contribution states that E · B and E^2 - B^2 are Lorentz invariants, explaining that if B=0 and E ≠ 0 in one frame, then this condition holds in all frames. They also note that if E · B ≠ 0 or if E · B = 0 and E^2 - B^2 < 0 in one frame, then there is no frame where B = 0.
  • One participant expresses a lack of understanding regarding the technical details provided by others.

Areas of Agreement / Disagreement

Participants do not appear to reach a consensus, as there are multiple competing views regarding the transformation of electric and magnetic fields and the implications for induced current.

Contextual Notes

The discussion includes complex theoretical concepts that may depend on specific assumptions about the nature of electric and magnetic fields and their invariants under Lorentz transformations. Some mathematical steps and definitions remain unresolved.

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Afaik there are configurations of the electric and magnetic field (dependent on the sign of [tex]E^2 - B^2[/tex], which cannot be transformed into purely electric configurations by a Lorentz transformation.
 
[itex]E \cdot B[/itex] and [itex]E^2 - B^2[/itex] are both Lorentz-invariants. If [itex]B=0[/itex] and [itex]E \neq 0[/itex] in one frame, then [itex]E \cdot B = 0[/itex] and [itex]E^2 - B^2 > 0[/itex] in that frame, and hence in all frames.

Also, if [itex]E \cdot B \neq 0[/itex] or if [itex]E \cdot B = 0[/itex] and [itex]E^2 - B^2 < 0[/itex] in one frame, then there does not exist a frame in which [itex]B = 0[/itex].
 
Last edited:
No comprende, but thanks for the effort.
 

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