I'm having a bit of trouble inserting the formulas in the answer window... How did you do it? I use the Formel Editor in MS Word, but it cannot copy it in here.
Anyway I didn't understand quite well...
Isn't the skalar product of (ct,x,y,z) with itsself the thing you wrote, but with +...
Hello, I have just registered in the forum!
I am a shool student, who is generally inerested in Physics and especially in Relativity.
So I'm reading a fascinating book about Einstein's theory at this moment (it's in German and it's called Newton, Einstein und die Relativitaetstheorie of...