Re: Space-time interval...

On 2024-08-16 06:55:31 +0000, Thomas Heger said:

Am Donnerstag000015, 15.08.2024 um 11:26 schrieb Mikko:

On 2024-08-13 13:10:33 +0000, Richard Hachel said:
 

Le 13/08/2024 à 13:38, Mikko a écrit :
 

In an orthogonal isometric coordinate system ds² = dt²-dx²-dy²-dz².

  Not really.
  ds² = dx²+dy²+dz²-dt²

 Both sign conventions are used. It doesn't matter as long as one knows
which one is used. The information content is the same anyway.
 If you represent vectors and position defferences with quaternions then
the real part of the square of the quaternion is ds² according to the
sign convetion that I used. But quaternions are rarely used in this
context so that is not important.

 Yes, becaause quaternions are the wrong construct, but quite close.

They are not wrong but 4-vectors are better for purpose.
--
Mikko