Alternative geometries.....

[geordief]

for describing the invariance of light.

As well as I understand  (which is poorly) when the invariance of light was discovered (by MM)  there were existing geometries that  were able to cope with it(sitting there more or less waiting for their relevance to be noticed)

 

Suppose they had not been around  are there any other methods  that could be used  to put down on paper what was being observed  (in a predictive way)?

 

Did anyone make any rudimentary attempts  before Minkowski spacetime blew them out of the water,so to speak?

 

I don't have any suggestions myself as I am very unskilled in the first place....

 

 

[studiot]

This is the weekend Geordie, so easy questions only please.

By alternative you mean alternative to what ?

By geometries you mean ...?

 

 

[Mordred]

@OP it may help to consider that the term invariance in this case means a measured quantity or value that will be the same for all observers measuring that quantity or value. For example rest mass is an invariant quantity. The variant quantity of mass is often called the relativistic mass. Light having no invariant mass.

I too am not sure how your describing geometries so will guess that you are referring to the geometries of a metric. However without knowing which properties of light you addressing this is just a guess.

 

[geordief]

1 hour ago, Mordred said:

@OP it may help to consider that the term invariance in this case means a measured quantity or value that will be the same for all observers measuring that quantity or value. For example rest mass is an invariant quantity. The variant quantity of mass is often called the relativistic mass. Light having no invariant mass.

I too am not sure how your describing geometries so will guess that you are referring to the geometries of a metric. However without knowing which properties of light you addressing this is just a guess.

 

Just the fact that all  observers in all inertial frames will measure the same speed of  propagation of any given light wave.

2 hours ago, studiot said:

This is the weekend Geordie, so easy questions only please.

By alternative you mean alternative to what ?

By geometries you mean ...?

 

 

Alternative to Minkowski spacetime diagrams I think (not necessarily successful but possibly different approaches)

Coincidentally I have  very recently come across one  which I am personally unable to judge the worth of 

https://www.quora.com/Why-is-the-speed-of-light-limited-Why-can-it-not-go-greater-than-its-approximate-velocity-3-10-8/answer/Eltjo-Haselhoff?share=ecbf35b4&srid=u1LaJ

''...which might serve as an  example ,no matter what ever flaws ,obvious or not it might have.

 

 

By geometries I will attempt " visual representations of the mathematical relationships between points in space or events in spacetime. "

In particular as they evolve in time  and incorporating points of observation from different (moving) points in the manifold  (if my terminology is at all correct)

[studiot]

Thank you for the interesting link, Geordie.

One thing I immediately noticed was the following

Quote

  As mentioned by others, the Universe has 4 dimensions. However, these are not three spatial dimensions and one time dimension, but four spatial dimensions, w, x, y and z. The fourth spatial dimension is perpendicular to x, y and z and it’s an ordinary spatial dimension, just like x, y and z. You could stick a ruler in it and measure it, if you could observe it. But you can’t see the w-dimension, and here is why.

The author replaces time as the fourth dimension, with a fourth space dimension, for his analysis.

That's all very well but he still admits only four dimensions.

Yet he goes on to talk about motion and velocity in his four dimensions, without apparently allowing time to have a status.

[Michael Wilkins]

Thank you for the interesting link, Geordie.