(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Hello everyone, thanks for reading.

This might be a little more math than physics (don't run away though!), but it's an excercise on my General relativity text :)

I need to prove that there exists an analog formula, like a*b = abcos(theta) for 3-vectors, only for 4-vectors, in which:

a*b= abcosh(theta), whereaandbare 4-vectors, a and b are defined: a = (-a*a)^-0.5, b = (-b*b)^-0.5, and theta is a parameter that describes lorenz boost between the frame where an observer whose world line points alongais at rest and the frame where an observer whose world line points alongbis at rest.

I have no idea how to work with this theta :-\

Thanks!

p.s.aandbare time-like 4 vectors.

2. Relevant equations

a*b= -a0*b0 + a1*b1 + a2*b2 = a3*b3

3. The attempt at a solution

I just tried to look for examples in the book and work with the definition... But I got nowhere :-\

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# Homework Help: Question in 4-vectors.

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