Discussion:
Q: Show that the spacetime interval (delta s) is invariant under the lorentz transfermations:
i.e. show that (c (delta t))^2 - (delta x)^s = (c(delta t'))^2 - (delta x')^2
delta s = s1 - s2
delta t = t1 - t2
delta x = x1 - x2
c= speed of light in a vacuum ; 's indicate a different system