The Speed of Light and of Galilean Relativity - Comments

[Laurie K]

Actually, calling the world line of a classical massless particle in SR a "photon path" is a huge misnomer.

The diagrams are not of world lines but more like the Optical Appearance plot used by Øyvind Grøn in the Fig 9 part C plot in his paper "Space geometry in rotating reference frames: A historical appraisal". http://areeweb.polito.it/ricerca/relgrav/solciclos/gron_d.pdf

 

[Orodruin]

The diagrams are not of world lines but more like the Optical Appearance plot used by Øyvind Grøn in the Fig 9 part C plot in his paper "Space geometry in rotating reference frames: A historical appraisal". http://areeweb.polito.it/ricerca/relgrav/solciclos/gron_d.pdf

This does not change the fact that calling them photon paths is a huge misnomer.

 

[haushofer]

It's a bit late, but I missed this reply. In my language they have the saying "better sometime than never", so here it goes.

Can you be more explicit? I wasn't aware that there was such a thing. Maxwell's equations are Maxwell's equations; they are Lorentz invariant, not Galilean invariant.

My point was, that when you want to consider elecotromagnetism in the non-relativistic limit (such that you obtain equations that are Galilei-covariant), the time derivatives of both fields drop out. Levy-Leblond (Nuovo Cimento B 14, 217-234) showed that these equations correspond to the limit c --> oo of the Maxwell equations. For an arxiv-link, see e.g.

https://arxiv.org/abs/1303.5608