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Do the electric and magnetic field change when we move from one frame to another?

Daniel Underwood
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user200068
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  • https://en.wikipedia.org/wiki/Classical_electromagnetism_and_special_relativity#The_E_and_B_fields – Nemo Jul 11 '18 at 06:04
  • Think of this intuitively. If I consider any vector from one reference frame to another, say from cartesian to polar, does the vector change? YES, it does change. What dosent change is its magnitude. – sbp Jul 11 '18 at 06:26
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    @sbp That's completely wrong in a number of ways. Changing the coordinate system from cartesian to polar is not an example of changing reference frames. The electric and magnetic fields are not vectors in special relativity (in the sense that they not transform as vectors, but as components of the electromagnetic field strength tensor). The magnitude of the E and B fields definitely does change between frames. – Chris Jul 11 '18 at 10:48
  • Absolutely. They are four vectors. I was just giving an intuitive explanation. – sbp Jul 11 '18 at 11:37
  • Related https://physics.stackexchange.com/q/341809/25301, https://physics.stackexchange.com/q/15879/25301 – Kyle Kanos Jul 12 '18 at 10:09

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Yes it changes . You can infer that from the formula for Lorentz force , F = q(V x B) + qE ,which implies for inertial observers who have non-zero relative velocities will measure different velocity of the charge and therefore they will end up calculating different forces if there is no transformation of electric and magnetic fields for different frames . Therefore there it changes and the changes are given by Lorentz transformations.

Lalithkumaar M
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    That isn't sufficient. Force also transforms under a Lorentz boost, so measuring a different force is expected. – Chris Jul 11 '18 at 10:50