How was Newtonian relativity ruled out in EM propagation?

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Discussion Overview

The discussion centers on the reasons why Newtonian relativity was not assumed for the propagation of electromagnetic (EM) radiation, particularly in light of Maxwell's equations and the implications of the Michelson-Morley experiment. Participants explore the relationship between light speed, reference frames, and the necessity of Lorentz transformations.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • One participant notes that the Michelson-Morley experiment made the luminiferous aether less likely but questions why light was not assumed to follow Newtonian relativity, suggesting that EM radiation should propagate at c + v based on relative velocities.
  • Another participant argues that the speed of light does not depend on the movement of the source, indicating that Lorentz transformations are necessary to account for this constancy.
  • A different participant emphasizes that accepting Maxwell's equations requires abandoning Galilean relativity, as Maxwell's equations are not invariant under Galilean transformations.
  • One participant references a specific section of a resource to support their claim about the relative velocities of induced fields and the expected speed of EM radiation.

Areas of Agreement / Disagreement

Participants express differing views on the implications of Maxwell's equations and the necessity of Lorentz transformations, indicating that multiple competing interpretations remain unresolved.

Contextual Notes

Some assumptions about the relationship between light speed, reference frames, and the implications of Maxwell's equations are not fully explored, leaving certain mathematical steps and definitions open to interpretation.

Zebulin
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What I've read on the Michelson/Morley experiment explains that it made the idea of the luminiferous aether seem less likely, but I don't think I've ever seen an explanation of why everyone didn't just assume that light follows normal Newtonian relativity. What I mean is this: according to Maxwell's equations, EM radiation is just propagating electric and magnetic fields. Those fields begin with an object that is moving at some velocity, v, with respect to the observer. Each induced field will be moving at the same relative velocity, so that the measured speed of the EM radiation will be c + v.

If this were the case, then you would expect the speed of light to be measured the same in all directions, regardless of the Earth's movement through space, and there would be no need for the Lorentz transformations. Can anyone tell me how this interpretation was ruled out?
 
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Precisely because the speed of light does not depend on the movement of the source, which is why the lorentz transforms are necessary.

Think that the length of the path of the light beam is different in different reference systems, if the speed of light remains constant then the time must also be different, so that the speed of light remains constant.

I c is a constant, then length and time must be different for different observers.
 
Zebulin said:
What I mean is this: according to Maxwell's equations, EM radiation is just propagating electric and magnetic fields.
Zebulin said:
t I don't think I've ever seen an explanation of why everyone didn't just assume that light follows normal Newtonian relativity.

If you accept Maxwell, you have to give up Gallilean relativity. Maxwell's equations are not invariant under Gallilean transforms.
 

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