Date: Jun 1, 2010 1:30 PM
Author: stargene@sbcglobal.net
Subject: Re: Is there a compact form for n-tuple relativistic additions of <br> velocities?

>

> iirc, the addition formula for the inverse hyperbolic tangent is the

> same as the addition formula for velocities in SR.

> i.e., atanh(x)+atanh(y) = atanh((x+y)/(1+xy)).

> Take tanh of both sides and have fun.

Thanks for your response.

Indeed, I looked it up and you are right. However, as I am

often preternaturally dense, I don't understand how knowing

that makes my task of adding, say, n = 10^6 identical little

velocities, where each one is v = Co / 10^6, (identically one

millionth the velocity of light) any easier without steam

shooting out of my ears.

Eg: How would taking the tanh of both sides of your relation

help me, and how does that take into account the totality of

all my n= 10^6 additions? And when n = 10^9 or more? :-(

Can you please enlighten me?

Gene